JP2019500596A - Light-based vehicle localization for mobile communication systems - Google Patents

Abstract

Techniques and structures for a mobile transportation system configured to determine the position of a vehicle within an area using light-based communication signals are disclosed. The system includes a plurality of luminaires located within an area and is configured to transmit luminaire position data identifiable by a sensor disposed in the vehicle. The sensor receives an image of the luminaire including a light-based communication signal encoded with the luminaire position data. The luminaire position data can be combined with the luminaire layout information so that a known position of the luminaire can be determined. The position of the vehicle relative to the known position of the luminaire can be determined based on a mathematical relationship. The orientation of the vehicle relative to the area can be determined based on an asymmetric reference pattern or a known position of the plurality of luminaires. The system can determine the position of the vehicle relative to the area by combining the position of the vehicle relative to a known position of a lighting fixture and the orientation of the vehicle relative to the area.

Description

  This application incorporates by reference the entirety of US Provisional Patent Application No. 62/262656, filed Dec. 3, 2015, and claims the benefit based thereon.

  The present disclosure relates to solid-state lighting (SSL) and, more particularly, to light-based communication via SSL.

  Indoor positioning systems typically use radio-frequency (RF) signals to facilitate navigation of buildings or structures. RF-based positioning is a communication signal for exchanging navigation and / or positioning information with one or more users of the system, such as ultra-wide band (UWB), BLUETOOTH®, ZIGBEE®. ) And Wi-Fi signals. These systems often include a number of RF transmitters (eg, BLUETOOTH® Beacon) located in or around the building and configured to communicate with the user. These transmitters can be located throughout the building to ensure sufficient access to the system.

  One embodiment of the present disclosure provides a method for determining a position of a vehicle in an area, the method comprising: receiving an image of an asymmetric reference pattern displayed by a luminaire in the area; Determining a coordinate position of the luminaire based on an image of the asymmetric reference pattern displayed by the luminaire, and based on an orientation of the asymmetric reference pattern in the received image, the vehicle relative to the area. Determining an orientation and determining a position of the vehicle relative to the area based at least in part on the determined coordinate position of the luminaire. In some cases, the determination of the position of the vehicle relative to the area is based at least in part on the position of the vehicle relative to the luminaire. In some other cases, the determination of the position of the vehicle within the area is based on a single received image of the asymmetric reference pattern displayed by the luminaire. In yet another case, determining the orientation of the vehicle relative to the area includes associating the asymmetry of the asymmetric reference pattern with a direction relative to the area. In some other cases, the determination of the coordinate position of the luminaire within the area is based on a luminaire identifier obtained from a received image of the asymmetric reference pattern. In yet another case, determining the position of the vehicle relative to the luminaire includes converting the determined coordinate position of the luminaire from a three-dimensional coordinate position to a two-dimensional position. In some such cases, the position of the vehicle relative to the luminaire is from the three-dimensional coordinate position of the luminaire to the image plane of the sensor, from the three-dimensional coordinate position of the luminaire to the sensor. By projecting a point along the projection line, the three-dimensional coordinate position is converted to the two-dimensional position.

  An example of another embodiment of the present disclosure provides a system for determining a position of a vehicle within an area, the system comprising a plurality of light sources configured to display an asymmetric reference pattern, wherein the asymmetric reference pattern A lighting fixture that indicates an orientation of the lighting fixture with respect to the area, a sensor disposed in the vehicle, configured to receive the asymmetric reference pattern, and a processor, the received Determining an in-area position of the luminaire based on an image of an asymmetric reference pattern; determining an orientation of the vehicle relative to the area based on the received asymmetric reference pattern; and determining the position of the luminaire And determining the position of the vehicle within the area based at least in part on the orientation of the vehicle relative to the determined area. It includes a processor configured. In some cases, the position of the vehicle within the area is based at least in part on the vehicle position relative to the luminaire. In some other cases, the vehicle is an autonomous vehicle configured to navigate the area using an image of the asymmetric reference pattern displayed by the luminaire. In yet some other cases, the asymmetric reference pattern is associated with a luminaire identifier, and the processor determines a light intensity value of one or more pixels of the received image to determine the luminaire identifier. The pattern can be decoded based on In some other cases, the processor is further configured to associate an asymmetry of the asymmetric reference pattern with a direction relative to the area. In some other cases, the luminaire includes a combination of an infrared light source and a visible light source, the asymmetric reference pattern is displayed using the infrared light source, and the area is illuminated using the visible light source. Is done. In some other cases, the system comprises a computing system in communication with at least one of a plurality of lighting fixtures and the vehicle via a network. In some other cases, the processor determines the position of the vehicle within the area based on a single image of the asymmetric reference pattern.

  An example of another embodiment of the present disclosure provides a method for determining a position of a vehicle in an area, the method receiving a first image of a first luminaire at a first position in the area; The first image includes a first visible light communication signal from the first lighting fixture; and a second image of a second lighting fixture in a second position different from the first position in the area; The second image includes a second visible light communication signal from the second lighting device, and the first lighting device in the area based on the first visible light communication signal displayed in the first image. Determining the first position, determining the second position of the second luminaire in the area based on the second visible light communication signal displayed in the second image, and determining The first and second positions, and the first and second positions Based on at least one of the selected pixels of the image, comprising the step of determining the position of the vehicle relative to the area. In some cases, at least one selected pixel of the first and second images is centered on at least one of the first and second luminaires displayed in the first and second images. Determined based on the pixel located at the pixel location. In some other cases, the step of determining the position of the vehicle relative to the area further includes the first and second images corresponding to at least one of the first and second luminaires, respectively. Associating at least one selected pixel with a first angle and a second angle; and determining a first distance in a first direction from the vehicle to the luminaire based on the first angle; Determining a second distance in the second direction from the vehicle to the lighting fixture based on the second angle, and determining at least one position of the determined first and second lighting fixtures, the first distance; And determining the position of the vehicle relative to the lighting fixture based on the second distance. In some other cases, the step of determining the first position of the first luminaire within the area further comprises determining a portion of the first image that includes the first luminaire; Analyzing the portion including the first luminaire in a first image to identify a visible light communication signal for the first luminaire, the visible light communication signal being encoded by a luminaire identifier; , Determining a position of the first lighting fixture based on the lighting fixture identifier. In yet some other cases, the portion of the first image comprises light intensity values of individual pixels of the first image, pixels associated with a background object and pixels associated with one or more luminaires. It is determined based on comparison with a threshold value to be distinguished. In some other cases, using the luminaire identifier to determine the location of the luminaire further includes receiving luminaire layout information in the area, the luminaire identifier and the luminaire layout information, Determining the coordinate position of the luminaire in the area by comparing and identifying the coordinate position of the luminaire. In some other cases, the step of determining the position of the vehicle relative to the area comprises the orientation of the vehicle relative to the area based on a first position of the first lighting fixture and a second position of the second lighting fixture. Including determining. In some other cases, determining the position of the vehicle relative to the area is based on a known distance between at least one of the first and second luminaires and a sensor disposed on the vehicle. .

  An example of another embodiment of the present disclosure provides a method for determining a position of a vehicle in an area, the method receiving an image of the area, wherein the image is in a first visible light communication (Visible Light communication). A first luminaire displaying a VLC signal and a second luminaire displaying a second VLC signal; determining a first pixel group of the image corresponding to the first luminaire; and Determining a second pixel group of the image corresponding to two luminaires, and a first of the first luminaires in the area based on the first VLC signal corresponding to the first pixel group of the image. Determining a position; and second of the second luminaire in the area based on the second VLC signal corresponding to the second group of pixels of the image. Determining a position; determining a direction of the vehicle relative to the area based on the determined first and second positions; and at least one of the determined first and second positions; And determining a position of the vehicle relative to the area based on a pixel selected from one of the first and second pixel groups of the image.

  The features and advantages described in this specification are not exhaustive, and many additional features and advantages will be apparent to one skilled in the art, especially in view of the drawings, specification, and claims. . Furthermore, it should be noted that the terms used herein are selected primarily for readability and teaching purposes and do not limit the scope of the technology of the present invention.

FIG. 6 is a perspective view of an area configured in accordance with an embodiment of the present disclosure.

FIG. 3 is a top view of an area configured in accordance with an embodiment of the present disclosure.

1 is a side view of an area including a vehicle and lighting fixture configured in accordance with one embodiment of the present disclosure. FIG.

1 is a schematic diagram of a vehicle receiver configured in accordance with an embodiment of the present disclosure. FIG.

1 is a bottom view of a luminaire configured in accordance with an embodiment of the present disclosure. FIG.

1 is a schematic diagram of a luminaire configured in accordance with one embodiment of the present disclosure. FIG.

It is a bottom view of the lighting fixture containing the visible light source and the infrared light source in one Embodiment of this indication.

FIG. 3 is a bottom view of a luminaire with an infrared light source disposed along the periphery of the luminaire in an embodiment of the present disclosure.

FIG. 3 is a bottom view of a luminaire having a diffuser disposed in front of a visible light source in an embodiment of the present disclosure.

1 is a block diagram of a system configured in accordance with an embodiment of the present disclosure.

5 is a flowchart of an exemplary method for determining a position of a vehicle relative to an area in an embodiment of the present disclosure.

1 is a bottom view of a luminaire configured in accordance with an embodiment of the present disclosure. FIG.

4 is a graph for determining a threshold between high and low intensity pixels of an image of a light-based reference pattern in an embodiment of the present disclosure.

FIG. 6 is a schematic diagram of a model for determining a relative position of a vehicle from a luminaire shown in a received image in an embodiment of the present disclosure.

FIG. 6 is a bottom view of a luminaire including a light pipe for generating an asymmetric reference pattern in an embodiment of the present disclosure.

1 is a bottom view of a luminaire configured in accordance with an embodiment of the present disclosure. FIG.

1 is a block diagram illustrating an example of a light-based communication (LCom) system configured in accordance with an embodiment of the present disclosure. FIG.

FIG. 3 is a block diagram illustrating an LCom-enabled luminaire configured in accordance with an embodiment of the present disclosure.

FIG. 6 is a block diagram illustrating an LCom-enabled luminaire configured in accordance with another embodiment of the present disclosure.

FIG. 4 is a diagram illustrating an example of any LCom signal that may be transmitted by an LCom enabled luminaire in an embodiment of the present disclosure.

1 illustrates an example of an LCom system that includes an LCom-enabled luminaire and a vehicle in an embodiment of the present disclosure.

FIG. 4 illustrates an exemplary graphic map of an LCom enabled luminaire deployed at a given venue and a corresponding LCom transmission indicating the location of that particular luminaire within the venue in one embodiment of the present disclosure.

6 illustrates an exemplary method for emitting location information from an LCom enabled luminaire in one embodiment of the present disclosure.

4 is a flowchart of an exemplary method for determining a position of a vehicle within an area in an embodiment of the present disclosure.

FIG. 3 is a schematic diagram of an area image including a lighting fixture and having a coordinate system in an embodiment of the present disclosure.

FIG. 6 is a schematic side view of an area showing a first angle associated with a pixel of a sensor in an embodiment of the present disclosure.

FIG. 6 is a schematic side view of an area showing a second angle associated with a pixel of a sensor in an embodiment of the present disclosure.

  These and other features of the present embodiments will be better understood by considering the following detailed description in conjunction with the figures described herein. The accompanying drawings are not drawn to scale. For clarity, not all components are labeled in each drawing.

  Techniques and structures for a mobile transportation system configured to determine the position of a vehicle within an area using static light illumination or light-based communication signals are disclosed. The system includes a plurality of luminaires located within an area and is configured to carry or otherwise transmit luminaire position data that is identifiable by a sensor disposed in the vehicle. The sensor receives an image of the luminaire and the displayed light-based communication signal in response to receiving the light-based communication signal. The vehicle position with respect to the area can be determined using the image. In some applications, the luminaire displays a static asymmetric reference pattern. The reference pattern illuminates the surrounding area of the luminaire, but also conveys luminaire position data (eg, luminaire identifier). The position data of the lighting fixture in the area can be determined by combining the position data of the lighting fixture with information on the layout of the lighting fixture in the area. The position of the vehicle relative to the luminaire can be determined based on the position of the known luminaire using mathematical modeling techniques. The asymmetric reference pattern also conveys the orientation of the luminaire relative to the area, which can then be used to determine the orientation of the vehicle relative to the area. Using the position of the vehicle relative to the luminaire and the orientation of the vehicle relative to the area, the system can determine the position of the vehicle relative to the area. The light-based communication signal, in other applications, is a visible light communication (VLC) signal generated by modulating the light intensity of one or more light sources of a luminaire. In such applications, the system is configured to determine the position of the luminaire based on an image of the VLC signal transmitted by the luminaire. The position of the luminaire can be determined by decoding the VLC signal received by the sensor. The vehicle position relative to the known luminaire position can be determined based on selected pixels of the image corresponding to the luminaire shown in the image. The vehicle orientation can be determined based on the position of the vehicle relative to the position of two or more known luminaires in the area. The position of the vehicle within the area can be determined based on the relative position of the vehicle from the position of the known luminaire and the orientation of the vehicle relative to the determined area.

(General overview)

  For example, indoor positioning systems for production or logistics applications that involve the automatic movement of materials and goods (eg, factories or warehouses) are high-level to ensure accurate movement of goods and / or equipment across an area. Need accuracy. Such systems often include mechanical or magnetic tracks, lasers, and visual objects (eg, signs, etc.) for guiding equipment through the area. Although these systems are accurate, they are generally fixed with respect to the area and cannot be easily adjusted. As a result, changing these systems can cause a temporary loss of system operation due to physical movement of parts.

  Other systems, such as radio frequency (RF) based localization systems are tunable but are often inaccurate. More particularly, RF systems such as UWB, BLUETOOTH®, ZIGBEE® and Wi-Fi are often prone to errors caused by, for example, multipath fading. Multipath fading occurs when a surface or object is included that reflects an RF signal transmitted to an area and produces a plurality of copies of the transmitted RF signal. This is particularly problematic in warehouses where there are many potential RF reflecting surfaces in a large area. Many of the reflected signals go through different paths and then change the characteristics used for navigation (eg, attenuation, phase shift, and transmission period) so that the navigation receiver can be structurally or destructively used. Interfering signals may be received. Therefore, the receiver may erroneously process the received positioning information and then provide inaccurate positioning information to the user.

  Thus, according to one embodiment of the present disclosure, techniques and structures for a mobile transportation system configured to determine a vehicle position within an area using light-based communication signals are disclosed. A mobile transportation system may be located in an area such as a warehouse or factory and may include a plurality of lighting fixtures disposed therein. The luminaire may be arranged at a specific coordinate position with respect to a reference point (for example, one corner of the area) and a reference axis (for example, x and y coordinate axes) located in the area in the entire area. The coordinate position of each luminaire is determined upon installation of the luminaire and provided to the system. The luminaire is configured to transmit luminaire position data recognizable by a sensor located in the vehicle. The vehicle, in some embodiments, is a fork truck or powered cart configured to move items and / or equipment throughout the area. The sensor is placed on the vehicle and as the vehicle moves through the area, the luminaire appears in the field of view (FOV) of the sensor. The sensor receives an image of the luminaire along with a light-based communication signal transmitted therefrom. In some embodiments, the sensor is a global shutter camera or a dynamic vision sensor. Using the image received by the sensor, the system is configured to determine the position of the vehicle relative to the area.

  In an exemplary embodiment, the luminaire displays a static asymmetric reference pattern. The reference pattern is generated by one or more light sources arranged in the luminaire and configured to send light to the area. The reference pattern can be generated by placing the light sources in a desired pattern in the luminaire and / or by changing the light intensity level of light emitted from one or more light sources. The reference pattern emitted by the light source illuminates the luminaire peripheral area but also carries luminaire position data. The luminaire position data is information such as a luminaire identifier that can be used to determine the vehicle position. The luminaire identifier can be combined with the luminaire layout information of the area to determine the luminaire location within the area for the luminaire shown in the image.

  The position of the vehicle relative to the area can be determined by first determining the position of the vehicle relative to the position of a known luminaire and determining the orientation of the vehicle relative to the area. For example, if the vehicle is located directly below the luminaire, the luminaire and the vehicle are positioned at the same position in the area. Thus, by determining the position of the luminaire as described above, the system also determines the position of the vehicle relative to the area. However, the vehicle is rarely positioned directly under the lighting fixture. Rather, the vehicle is more often positioned at a distance relative to the luminaires in the area. In such cases, the position of the vehicle relative to the luminaire can be determined based on the position of the known luminaire using a mathematical modeling technique such as a pinhole camera model. The asymmetric reference pattern also conveys the orientation of the luminaire relative to the area. The system is configured to recognize the asymmetry of the reference pattern and relate it to the direction with respect to the area (eg, the main magnetic field direction or any coordinate system direction defined by the area). The orientation of the vehicle with respect to the area can be determined based on the reference pattern in the received image and the orientation of the received reference pattern with respect to the area (for example, the asymmetric reference pattern faces north). By combining the determined vehicle position (eg, (x, y) coordinates) relative to the luminaire with the vehicle orientation relative to the area, the system can determine the position of the vehicle relative to the area.

  The mobile transportation system, in other embodiments, communicates luminaire position data using visible light communication (VLC) signals. The VLC signal is generated by modulating one or more light sources of the luminaire. In an exemplary embodiment, a sensor located on the vehicle is placed at a distance from the luminaire and receives an image of the luminaire along with the received VLC signal. The VLC signal is encoded with a luminaire identifier (eg, a luminaire identification number) recognizable by the system. In some embodiments, the luminaire identifier can be encoded into the VLC by converting the identifier from a piece of information or by commanding the VLC light signal. In order to convert the luminaire identifier to an optical signal, the system can transmit a VLC optical signal at a specific frequency and / or light intensity level corresponding to the specific luminaire identifier. The system is now configured to decode the VLC signal to obtain a luminaire identifier. The luminaire identifier can be combined with the luminaire layout information to determine the location (eg, coordinate position) of the luminaire within the area.

  As described above, when the vehicle is located directly under the luminaire, the position of the luminaire and the position of the vehicle are the same with respect to the area. To determine the position of the vehicle relative to the position of the known luminaire (eg, when the vehicle is placed adjacent to the luminaire), the system determines the relative vehicle position based on the selected pixels of the image. Configured to determine. More particularly, the system is configured to associate two angles (eg, horizontal and vertical angles) with each pixel location in the received image. These angles are determined by calibrating sensors located on the vehicle and then fed to the system or programmed. The system is configured to select a pair of angles based on selected pixels of the image corresponding to the luminaire.

  The system is configured to process the image and determine pixels corresponding to the luminaire in the image. In an exemplary embodiment, the system distinguishes between image pixels corresponding to luminaires and other pixels corresponding to background objects by determining a light intensity value for each pixel of the received image. Background objects are objects in the sensor's FOV that do not provide luminaire position data; ceiling tiles, plumbing, ducts, and structural beams are some examples. In some embodiments, the image pixel corresponding to the luminaire is determined using a threshold based on the pixel light intensity value. The pixel light intensity value is a number that indicates the level of light at a given pixel of the image. The threshold is a pixel intensity value that can be used to distinguish between pixels associated with the luminaire and other pixels corresponding to the background object. The system is configured to identify a pixel corresponding to a background object when the pixel light intensity value is below a threshold value. A pixel light intensity value equal to and / or above the threshold indicates a pixel corresponding to the luminaire. Many other image processing techniques may also be used in light of this disclosure.

  For image pixels corresponding to the identified luminaire, the system is further configured to select a pixel corresponding to the luminaire to determine a vehicle position relative to a known luminaire position. In an exemplary embodiment, the system is configured to analyze a pixel of the image corresponding to the luminaire and select one pixel corresponding to the luminaire of the received image, which pixel is then from the luminaire. Can be used to determine the relative vehicle position. The selected pixel may be determined in any one of several ways. For example, in some embodiments, a local scan is performed by determining a pixel located at the center pixel location of the luminaire shown in the image using grid analysis techniques or by representing the center of mass of the luminaire. Including selecting. In other embodiments, the local scan includes selecting the pixel associated with the maximum pixel light intensity value. Once selected, the system is configured to select a pair of angles associated with the pixel location of the selected pixel. With the pixel corresponding to the luminaire and the selected pair of angles, the system is configured to determine the position of the vehicle relative to the luminaire. Since the sensor located on the vehicle is at a certain distance from the luminaire, the position of the vehicle relative to the luminaire can be determined based on the geometric relationship between the system components (eg, sensor and luminaire).

  To determine the vehicle position (eg, global coordinate position) relative to the area, the vehicle orientation relative to the area is combined with the vehicle position (eg, local coordinate position) determined relative to the luminaire. Without the vehicle orientation, the position of the vehicle relative to the luminaire can be in either of two positions (eg, facing the first side of the luminaire or the second side of the luminaire). Faced). In an exemplary embodiment, the system determines the position of several luminaires and the relative vehicle distance therefrom to determine the orientation relative to the area to determine the vehicle distance relative to the luminaire position. And is configured to obtain a unique combination.

(Example mobile transportation system application)

  FIG. 1A is a perspective view of an area 10 that can be any structure or spatial environment in which a mobile transportation system such as a warehouse or factory exists. In such an environment, for example, a mobile transportation system such as a fork truck or a powered cart moves items throughout the area 10. In order to place the articles at the desired location, the mobile transportation system is configured to determine their particular location within the area 10. 1 includes a floor 40, a wall 60, a shelf 80, a vehicle 90, and lighting fixtures 100A and 100B (collectively referred to as the lighting fixture 100).

  In this example, area 10 includes a floor 40 and walls 60 for accommodating containers stored in shelves 80. The floor 40 generally supports the vehicle 90 while moving in the area 10. In some embodiments, the floor 40 is a flat surface and has a known distance C (shown in FIG. 2A) from the luminaire 100. The distance C can be programmed into the system for use in determining the vehicle position within the area 10, as will be further described. As illustrated, in the exemplary embodiment, wall 60 is disposed along the perimeter of floor 40, thereby defining the layout of floor 40. In other embodiments, the wall 60 is a pillar disposed throughout the floor 40. Regardless of their configuration, the floor 40 and the wall 60 together define an area 10 through which the vehicle 90 passes to transport items.

  In some embodiments, the vehicle 90 may be an indoor transport such as, for example, an automated forklift or robot. For example, as one use case, area 10 is a large stock room or so-called fulfillment center that includes hundreds or thousands of shelves with stocked items placed in known locations, The goods are accessible via a programmed robotic vehicle so that the goods can be removed and returned to a packing station where a person packs the goods and ships them to the purchaser. In other embodiments, the vehicle 90 may be an autonomous vehicle, in which case the area 10 is a corridor, a parking lot or a road (either indoors or outdoors). An autonomous vehicle refers to a vehicle that can sense and navigate its environment without human input (for example, a person who physically operates a set of vehicle control devices). In an exemplary embodiment where the system is configured to communicate luminaire position data via VLC signals, the vehicle 90 is a known distance (eg, as shown in FIG. 2A) from the luminaire 100, as further described. At a distance Z.) configured to move along a floor 40 (eg, warehouse floor, hallway or road). In other embodiments of the present disclosure, the distance of the vehicle 90 from the luminaire 100 may not be constant. For example, in some embodiments where luminaire position data is communicated via an asymmetric reference pattern, the vehicle 90 can move in any direction (eg, up, down, back and forth, left and right) relative to the area 10. . Further, the receiver 208 disposed on the vehicle 90 can move relative to the center line of the main body 204 (eg, in the pitching, yawing, and rolling directions). Unlike conventional systems that include a mechanical or magnetic trajectory guidance system that guides the movement of the vehicle along a predefined path, the vehicle 90 is not so limited. Rather, the vehicle 90 is configured to move freely within the area 10 using location information provided by one or more lighting fixtures 100. Many attributes and configuration elements of the vehicle 90 are understood in light of this disclosure.

  The vehicle 90 navigates the area 10 using position information received from one or more lighting fixtures 100. The luminaire 100 is configured to send light to illuminate the area 10 using one or more light sources such as light emitting diodes (LEDs). The luminaire 100 is further configured to display an asymmetric light-based reference pattern for use in vehicle positioning. An asymmetric light-based reference pattern is a pattern of light sources configured to communicate position information, such as a luminaire identifier, and is used to determine the position of the vehicle within area 10 when decoded by the system. be able to. The asymmetric pattern is formed by creating a pattern by physically placing individual light sources within the luminaire 100, as described further, or operating the light sources within the luminaire 100 at various light intensity levels. And can be formed by creating an asymmetric pattern.

  The luminaire 100 is disposed within the area 10, for example, attached to the ceiling or otherwise secured, so that the luminaire 100 is visible from the vehicle 90. More specifically, the luminaire 100 is placed at a known distance on the floor 40 (eg, distance C shown in FIG. 2A). In some embodiments, the luminaire 100 enters the ceiling to maintain a desired height between the luminaire 100 and the vehicle 90. In other embodiments, the luminaire 100 is attached to a part of a building structure, such as a wall 60. In a more general sense, the luminaire 100 can be placed on any surface of the area 10 so that it is visible to the vehicle 90 at a known height above the floor 40.

  FIG. 1B is a top view of area 10 showing an exemplary arrangement of the luminaire 100 shown in FIG. 1A. As shown, the luminaire 100 can be placed throughout the area 10 to provide vehicle location information to many different area locations. In the exemplary embodiment, the coordinate position (eg, (X, Y)) of each luminaire 100 with respect to area 10 may be determined during the luminaire installation stage using a reference frame such as floor 40. In the exemplary embodiment, the luminaire 100 is within an area using a first reference axis 45A along the X direction and a second reference axis 45B along the Y direction (collectively referred to as reference axis 45). Placed in. The floor 40 includes, for example, a reference point 47 located at a corner of the floor 40, from which the luminaire 100 can be placed. The position of each lighting fixture 100 in the area 10 with respect to the reference point is known as lighting fixture layout information. This information is stored in the memory of the vehicle 90 and / or computing system, and that information can be accessed to determine the position of the vehicle. Once determined, the coordinate position of the luminaire 100 can be combined with other known distances (eg, the Z distance of FIG. 2A) to determine a three-dimensional luminaire coordinate position within the area 10.

  The luminaire 100 can be arranged so that multiple vehicles at different locations in the area 10 can observe the same luminaire 100 and receive the luminaire position data, which in turn is unique to each vehicle. Can be used to determine the position of. Luminaire position data is any information such as optical communications (eg, a reference pattern representing a luminaire identifier), RF, and infrared (IR) signals that can be used to determine the vehicle position. As a result, a single luminaire 100 can provide its luminaire position data to multiple vehicles at once, avoiding the vehicle 90 experiencing communication errors due to multiple received signals. In the exemplary embodiment, the luminaire 100 is arranged in a grid pattern on the floor 40 with respect to the xy coordinate axes. However, in other embodiments, the luminaires 100 are arranged in a straight line when placed along a corridor or passage, or along a circular pattern around a central location within the area 10. . In a more general sense, the luminaire 100 can be configured in any desired arrangement so that the vehicle 90 can determine the vehicle position within the area 10 based on the luminaire coordinate position.

  FIG. 2A is a side view of an area including a vehicle 90 and a lighting fixture 100 configured in accordance with one embodiment of the present disclosure. The vehicle 90 includes a body 204 configured to carry articles and equipment through the area 10. In the exemplary embodiment, body 204 is a fork truck. In other examples, the body 204 may be a robot or a power driven cart. The body 204 maintains a constant distance A relative to the floor 40 in some embodiments. The main body 204 is attached with a receiver 208 that receives position data of the lighting fixture. Receiver 208 is located at a known distance B relative to floor 40. As illustrated, the luminaire 100 is located a distance C away from the floor 40. Since both distances B and C are measurable and are known values, these distances can be used to determine the distance Z from the receiver 208 to the luminaire 100. Combining the distance Z and the coordinate position of the luminaire (as described with respect to FIG. 1B), the three-dimensional position of the luminaire can be determined. The three-dimensional position of the luminaire can be programmed into the system and used to determine the vehicle position relative to the luminaire, as further described. However, it should be noted that changes in distance A and / or distance B due to the rise, fall, and / or tilt of the body 204 can adversely affect the determined vehicle position.

  FIG. 2B shows an exemplary receiver 208 configured in accordance with one embodiment of the present disclosure. The receiver 208 includes one or more sensors 212, a processor 216, a memory 220, and a transceiver 224 that collectively receive and process luminaire position data as the vehicle changes its position. The receiver 208 can be placed at any location on the body 204 so that the at least one sensor 212 can receive a reference pattern displayed as a predetermined luminaire 100. As seen in the exemplary embodiment, receiver 208 is located on top of vehicle 90. Other embodiments of the receiver will be apparent in light of this disclosure.

  Receiver 208 includes one or more sensors 212 configured to receive or otherwise process an image of a light-based reference pattern displayed by a given luminaire 100. In the exemplary embodiment, sensor 212 is attached to body 204 to maintain sensor 212 at a distance from luminaire 100. In some embodiments, sensor 212 is a complementary metal-oxide semiconductor (CMOS) sensor that is sensitive to light in both the visible and infrared spectrum. In other embodiments, sensor 212 may be a charge-coupled device (CCD) image, a global shutter camera, or a dynamic visual sensor. In a more general sense, sensor 212 can be any sensor that can withstand the effects of industrial environments, such as being able to meet continuous exposure to vibration and use and / or meet applicable safety standards. it can.

  Sensor 212, in some other embodiments, includes a filter, such as an infrared or polarizing filter, to detect signals transmitted at a different wavelength and / or direction than the ambient light present in the area. The filter may reduce the intensity of visible light so that the sensor 212 does not become able to detect the signal displayed by the luminaire 100 due to saturation with ambient light. The tunable optical filter is implemented in other embodiments to generate two different modes of operation: (1) IR light enhancement and visible light reduction (2) Visible light enhancement and IR light Reduction. The filter is configured to be adjustable to improve the accuracy of the sensor 212 in one or more applications.

  Further, in some embodiments, sensor 212 is calibrated before and during use. Sensor calibration can include using the sensor 212 to receive or otherwise process multiple images of the reference pattern at various known distances and angles. Using these known distances and angles, the receiver 208 can be adjusted to achieve a high level of accuracy during use. Once calibrated, the sensor 212 may be periodically calibrated to maintain the desired level of accuracy of the system.

  The sensor 212 transmits this data to the processor 216 in response to receiving an image of the asymmetric light-based reference pattern, which is programmed or otherwise configured to compile and distribute the instructions and data. Has been. For example, in some embodiments, the processor 216 is configured to determine a luminaire identifier from an asymmetric reference pattern of the received image. The processor is further configured to calculate a vehicle position relative to the luminaire 100 based on the determined luminaire identifier, as further described. To calculate the position of the vehicle within area 10, the processor accesses or otherwise executes positioning firmware and software, such as routines and subroutines, and analyzes the received images to analyze luminaire position data ( For example, it is configured to extract a luminaire identifier. Once determined, the processor is configured to transfer vehicle position data to memory 220, which data is maintained for future use by the system (eg, for vehicle tracking purposes). Can do.

  As shown, the receiver 208 further includes a memory 220 that is accessible by the processor 216. In the exemplary embodiment, data created and / or managed by processor 216 is stored in memory 220 to support various operations of vehicle 90. Data such as images, area maps, luminaire identifiers, and lookup tables are made accessible to the processor 216 via the memory 220 and / or the network, thereby determining the location of the vehicle. Memory 220 may be of any suitable type (eg, RAM and / or ROM, or other suitable memory) and size, and in some cases, volatile memory, non-volatile memory, or combinations thereof. May be implemented. The memory 220 may also be any physical device capable of non-transitory data storage, such as a plurality of instructions that, when executed by one or more processors, facilitates operation of the electronic device according to a process. It may be a computer program product that includes one or more non-transitory machine-readable media that encode.

  Receiver 208 further includes, or is otherwise operatively coupled to, transceiver 224 that receives and transmits communication signals for exchanging information between receiver 208 and other devices in the system. Is done. For example, the transceiver 224 may be located in the receiver 208, or may be operatively coupled in other ways, and may be one or more other located within and / or outside the area 10. It may be configured to communicate with the transceiver. In some embodiments, the transceiver is an RF signal antenna for transmitting data to and receiving data from the communication network. The communication signal includes various information such as, for example, protocol information, images, reference pattern data, luminaire identifiers, system measurements, and / or reference pattern decode commands / commands that can be used to determine vehicle position within the area. be able to.

(Light-based reference pattern vehicle location)

  As previously mentioned, vehicle localization systems that include magnetic tracks and / or mechanical tracks are relatively restrictive and limit vehicle movement throughout the area. Furthermore, systems that transmit information via RF signals are prone to errors due to the reception of inaccurate communication signals. The present disclosure addresses these issues by determining the vehicle position using light-based communication signals. In an exemplary embodiment described in more detail below, the system uses a light-based communication signal in the form of an asymmetric reference pattern to communicate luminaire position data and luminaire orientation relative to the area. To do. As a result, the vehicle can move within the area under 6 degrees of freedom (eg, up / down / left / right, front / rear, pitching, rolling and yawing). The system is further configured to process the luminaire position data to determine a global vehicle position (eg, xy coordinate position) for the area to guide and / or track vehicles throughout the area. . In the example, the global position of the vehicle relative to the area can be determined using a single image of the asymmetric reference pattern.

(System structure and operation)

  FIG. 3A shows a bottom view of a luminaire 100 configured in accordance with one embodiment of the present disclosure. The luminaire 100 is configured to send luminaire position data along with light for illuminating the area 10, and the luminaire position data can be used, for example, to determine a vehicle position within the area 10. The luminaire identifier transmitted using the reference pattern. As a result, luminaire location data may be communicated without potential degradation such as environmental interference from signs and stickers, breakage, tearing, and dirt (which are common in industrial environments). it can.

  The luminaire 100 is configured to store and operate a number of visible light sources 308 for transmitting visible and infrared light. In the exemplary embodiment, luminaire 100 includes a housing 304 for housing one or more visible light sources 308. The housing 304 has a rectangular form factor in some embodiments. However, in other embodiments, the housing 304 can employ a hexagonal or diamond-shaped form factor. In a more general sense, the housing 304 can be any shape that can maintain the visible light source 308 in a fixed position.

  Within the housing 304, a number of visible light sources configured to generate and transmit light, eg, light emitting diodes (LEDs), in an asymmetric reference pattern encoded with luminaire position data (eg, luminaire identifier). There are 308. The data is converted from a piece of information into an asymmetric reference pattern based on light by illuminating the light source of the luminaire as described herein. Visible light source 308, in some embodiments, is configured to operate with a short duty cycle (eg, 100 milliseconds) or using a low current level. In other embodiments, the light source 308 is configured as a dimmable light source to display an asymmetric reference pattern at a number of different light intensity levels to vary the illumination of the area.

  The asymmetric shape of the reference pattern can be generated based on the physical arrangement of the light sources 308 in the luminaire 100. In some examples, low cost options such as solder connections or conductive adhesives are used to attach the individual light sources 308 in a pattern so that the luminaire identifier is displayed when the light sources 308 are illuminated. be able to. In some embodiments, the reference pattern is reconfigurable so that the reference pattern displayed by the light source 308 communicates various types of information (eg, commands, navigation information, weather forecasts, and emergency information). To be corrected. For example, in some embodiments, the light source 308 can be relocated to a different location within the housing 304 to generate a different reference pattern.

  FIG. 3B is a schematic diagram of a luminaire 100 configured in accordance with one embodiment of the present disclosure. In addition to their position, the visible light source 308 can be operated to generate an asymmetric reference pattern regardless of whether the physical arrangement of the light source 308 corresponds to the asymmetric pattern. In some embodiments, the luminaire 100 includes a resistor, such as an OR resistor, operatively coupled to the light source 308 to generate a luminaire identifier. This is illustrated in FIG. 3B, where the luminaire 100 includes power supplies 309A and 309B (collectively referred to as 309), each power supply 309A and 309B powering the combination of light source 308 and resistor 310 via an electrical circuit. (Eg, circuits “A” and “B”). Since circuits A and B are mounted parallel to each other in various sections 311A-E (collectively 311) of luminaire 100, a portion of circuit A has a light source 308 in a section, eg, section 311A. If so, circuit B has a resistor located in the section. When power is supplied to circuits A and B, each visible light source 308 generates a portion of the luminaire identifier so that the entire light source 308 of circuits A and B represents the identifier. It should be noted that the circuits A and B should be placed as close as possible to each other in the luminaire 100 in order to improve accuracy.

  In some embodiments, a switch is operably connected to each power supply 309 to control the flow of electricity through circuits A and B and thus control how an asymmetric reference pattern is displayed. In the exemplary embodiment, the controller is connected to a switch, such as a driver, and is configured to control the operation of light source 308 by manipulating the switch. In other embodiments, the switch is configured as a full bridge, whereby there are four switches that regulate the supply of power to the light source 308 in response to input from the controller. Regardless of their configuration, the switch controls the power to circuits A and B, and thus controls how the reference pattern is displayed. In the exemplary embodiment, alternating power is applied to each of circuits A and B so that the system can distinguish between light source 308 of circuit A and light source 308 of circuit B to decode the asymmetric reference pattern. be able to. For example, during the first half of the operating cycle of the luminaire, circuit A is powered, the light source connected to circuit A emits light, and the light source 308 connected to circuit B does not emit light. In the second half of the cycle, power is no longer supplied to circuit A, so the light source 308 of circuit A no longer emits light. On the other hand, because circuit B receives power, light source 308 associated with circuit B emits light. In such a case, the system is configured to associate the light source 308 of circuit A with a first value, such as “1” in binary form. The system is also configured to associate the light source 308 of circuit B with a second value different from the first value, eg, “0” in binary form. In addition, in some embodiments, the visible light sources 308 can be arranged in different orientations, such as 180 degrees relative to each other, to generate different bits of information (eg, a 0 degree light source is “1”). The 180 degree light source is “0”). In order to distinguish which circuit is transmitting during each half cycle of the lighting circuit operation, several visible light sources 308 may indicate each other to indicate the type of content (eg, “1” or “0”). Are arranged spatially (for example, arranged in close groups). With each determined half-cycle content type, the system is configured to analyze the received image to determine encoded luminaire position data. In some embodiments, the sensor is synchronized with the timing of the visible light source 308 such that multiple light signals within a single image are distinguished from each other.

  In other embodiments, the asymmetric reference pattern is generated by the operation of the light source 308 rather than the light source position within the luminaire. In the exemplary embodiment, the reference pattern is created by a combination of active (ie, turned on) and inactive (ie, turned off) visible light source 308. In such a case, a binary value of “1” is assigned to the active light source, and a binary value of “0” is assigned to the inactive light source. In other embodiments, the reference pattern is created using a light color or a combination of a light color and an active visible light source 308. Regardless of its configuration, the asymmetric light-based reference pattern conveys luminaire position data in a manner that is inconspicuous for people in area 10.

  However, a reference pattern created using an inactive light source is provided by the luminaire 100 because only some of the visible light sources 308 emit light while the reference pattern is displayed. Reduce the lighting level. To remedy this drawback, in the exemplary embodiment, luminaire 100 is configured to create a reference pattern based on a change in light intensity level of light source 308. In the exemplary embodiment, the luminaire 100 is configured in two modes of operation: (1) full light emission mode and (2) message mode. When operating in a full emission mode, the luminaire 100 is configured to output a maximum amount of light within the field of view (FOV) of the luminaire 100. The maximum light intensity may be defined by physical component capabilities (eg, maximum LED power) or program limits imposed by system operating software. Regardless of how the maximum amount of light is defined, the full emission mode provides a sufficient amount of light so that the vehicle can navigate below and near the luminaire 100.

  However, during the message mode, the luminaire 100 outputs less light and generates a reference pattern. More particularly, the reference pattern is created in this exemplary embodiment by changing the light intensity level of the visible light source 308. This can be seen from FIG. 3A, where some of the visible light sources 308 operate at a high light intensity (indicated by a shadowless box) and other visible light sources 308 have a low light intensity level (shadowed). (Indicated by a box). By creating a reference pattern having a visible light source 308 with various light intensities, all the visible light sources 308 emit light in the luminaire 100. Greater illumination can be provided. Furthermore, the reference pattern can be reconstructed by changing the light intensity level of the visible light source 308 to generate a different reference pattern. In an exemplary embodiment, a visible light source 308 operating at a higher intensity level (eg, a maximum intensity level) can be assigned a value of “1” in binary format. A visible light source 308 that operates at a lower light intensity level can be assigned the value “0”, so that the light source 308 is luminaire position data in the form of a binary message that can be decoded as described (eg, 0101110). To determine the position of the vehicle relative to the luminaire 100. The lower light intensity level may range from 50%, 65%, 70%, 85%, 90%, 93% and 95% of the higher light intensity level for a given luminaire 100. In a more general sense, the difference between the higher and lower light intensity levels must be as small as possible to provide the maximum amount of illumination, so that the reference pattern is still recognizable. Should be large enough. Furthermore, the smaller difference between high and low light intensity levels creates a reference pattern that is less noticeable for people in the area.

The amount of information transmitted by the reference pattern depends on the number of visible light sources 308. Each light source 308 emits light that can be processed as bits of information (eg, “1” or “0”). Together, several visible light sources 308 form a reference pattern that represents a message (eg, 010011101) composed of several bits of information. Accordingly, the luminaire 100 is configured to generate a number of reference patterns equal to 2 ⁿ , where n is the number of visible light sources 308 and is in binary form. However, in other embodiments, the luminaire 100 is configured to change not only the light intensity level, but also the light color. A color encoding scheme that changes the light color may be used by the luminaire 100 to generate a number of other reference patterns that are recognizable by vehicles in the area. The illumination position data included in such a reference pattern can be extracted by reading the pixel RGB values of the reference pattern image. Accordingly, the luminaire 100 is configured to generate a reference pattern using light intensity, and the color can generate a total number of 262,144 reference patterns.

  FIG. 3C is a bottom view of the luminaire 100 including a visible light source 308 and an infrared light source 312 according to one embodiment of the present disclosure. Changing the light intensity level of the visible light source 308 is technically complex and may require software and / or hardware such as a driver. Accordingly, the luminaire 100 may include a plurality of infrared light sources 312 for displaying a reference pattern in some embodiments. In such embodiments, the reference pattern is displayed without limiting or adversely affecting the level of visible light emitted by the luminaire 100 to illuminate the area. As seen in FIG. 3C, the infrared light source 312 is mixed with a visible light source 308 in an exemplary embodiment, and the infrared light source 312 is arranged in an asymmetric pattern to convey luminaire orientation and position data. The On the other hand, the visible light source 308 is arranged to illuminate the area 10. The visible light sources 308 are arranged in a symmetric pattern in some embodiments to provide a uniform illumination level. In this exemplary embodiment, each of the infrared light source 312 and visible light source 308 has its own separate power electronics, but this is not required. In other embodiments, a single electronic circuit can provide power to both the visible light source 308 and the infrared light source 312. In another example, the luminaire 100 is configured such that the infrared light source 312 is disposed within the housing 304 along the periphery of the opening 316 and the infrared light source 312 is separated from the visible light source 308.

  FIG. 3D is a bottom view of the luminaire 100 with infrared light sources 312 and 320 disposed along the outer periphery of the luminaire 100, according to one embodiment of the present disclosure. In the exemplary embodiment, luminaire 100 emits light to illuminate the area and communicates non-positioning information (eg, emergency information) in addition to the positional information transmitted by infrared light sources 312 and 320. A visible light source 308 configured to display a reference pattern is included. More specifically, the infrared light sources 312 and 320 are installed within the housing 304 and generate a unique asymmetric pattern that can be decoded by a system (eg, a vehicle) to determine the vehicle position within the area. In the exemplary embodiment, infrared light sources 312 and 320 can be made from a pre-fabricated roll of flexible material, such as tape. The luminaire position information is transmitted based on the distance between the infrared light sources 312 and 320. The reference pattern includes both infrared light sources 312 and 320, but not always. However, the reference pattern in other embodiments can be simply made with the infrared light source 312. Regardless of the light source used, the reference pattern created by the infrared light sources 312 and 320 can be displayed continuously regardless of whether the visible light source 308 is activated.

  In addition to the luminaire position data, the luminaire 100 is further configured to communicate position information of the luminaire 100 relative to the area. Luminaire orientation information is any data and / or signal that can be used to determine how a given luminaire 100 is positioned relative to an area. For example, the infrared light source 320 is configured to transmit an optical signal that can be decoded to determine the orientation of the luminaire 100 relative to the area. In such a case, the infrared light sources 320 together form a prototype that indicates the direction of the luminaire 100 relative to the area (eg, north). In other examples, the prototype can include infrared light sources 320 disposed on two or more sides and / or opposite sides of the luminaire 100. Regardless of their configuration, the system is configured to recognize a prototype and associate a corresponding direction as described further.

  FIG. 3E is a bottom view of the luminaire 100 with the diffuser 324 positioned in front of the visible light source 308 according to one embodiment of the present disclosure. In some embodiments, the luminaire 100 may include or be coupled to other devices, such as a diffuser 324, to improve the lighting experience. In the exemplary embodiment, a diffuser 324 is mounted or otherwise disposed between the visible light source 308 (visible light source 308 is indicated by a dashed line) and the area. However, if the diffuser 324 is placed in front of the infrared light sources 312, 320, the transmission of the infrared signal can be adversely affected if the infrared signal is at a frequency that can be filtered by the diffuser 324. As a result, part of the reference pattern may not be visible in the image, and as a result, the pattern may be incomplete and / or inaccurate. In order to avoid inaccuracies caused by the diffuser 324, the infrared light sources 312 and 320 are located on the outer periphery of the luminaire 100 and are not covered by the diffuser 324, as shown in FIG. 3E. In other embodiments, the contour or shape of the diffuser 324 is configured to convey information for determining the position of the luminaire, such as conveying the orientation of the luminaire based on an asymmetric shape, for example. Regardless of its configuration, the diffuser 324 is configured to scatter light to provide a soft light appearance in the area.

  FIG. 4 is a block diagram of a system 400 configured in accordance with one embodiment of the present disclosure. System 400 includes area 10, network 404, and computing system 408. Area 10 includes luminaire 100 for transmitting luminaire position data to vehicle 90 as previously described in connection with FIG. 1A.

  As shown, system 400 enables communication communication with network 404 and one or more servers or computer system 408. Network 404 may also communicate with computer system 408 (as described herein) to place luminaire 100 and / or vehicle 90. Network 404 may be a wireless local area network, a wired local network, or a combination of local wired and wireless networks, and may further include access to a wide area network such as the Internet or a campus wide network. In a more general sense, the network 404 can be any communication network.

  According to some embodiments, the computing system 408 may be any suitable computing system capable of communicating via a network 404, such as a cloud-based or local server computer, and the vehicle location service May be programmed to provide For example, the vehicle location related service is configured such that the computing system 408 transmits the layout of the lighting fixtures in the area 10 to the vehicle 90 (eg, lighting that cross-references the location in the area 10 and the identification number). Equipment list). Many other such configurations will be apparent in light of this disclosure.

  Computing system 408 further includes or is operatively coupled to transceiver 412 that receives and transmits communication signals to facilitate the exchange of information between computing system 408 and other devices in system 400. May be. The transceiver 412 may be located, for example, within the computing system 408 and may be operably coupled to communicate with one or more other transceivers located inside and / or outside the area 10. It may be configured to. In some embodiments, the transceiver 412 is a modem or other suitable circuit that allows data to be transmitted and received from a network, such as the network 404. The communication signal can include various information such as, for example, protocol information, images, reference pattern data, system measurements, and / or reference pattern commands / commands.

  Upon receiving data from the luminaire 100 and / or the vehicle 90, the transceiver 412 can transmit the data to the processor 416, which is programmed or configured to compile and distribute the instructions and data. For example, in some embodiments, the processor 416 is configured to update a database of luminaire data in response to receiving a new luminaire identification number. The luminaire data may be transmitted to one or more vehicles 90 (as described below) via the network 404 in some embodiments to determine the vehicle location.

  As shown, computing system 408 further includes memory 420 that is accessible by processor 416. Data created and / or managed by processor 416 may be stored in memory 420 to support the operation of computing system 408. Memory 420 may be of any suitable type (eg, RAM and / or ROM, or other suitable memory) and size, and in some cases, volatile memory, non-volatile memory, or combinations thereof. May be implemented. The memory 420 may also be any physical device capable of non-transitory data storage, such as a plurality of instructions that, when executed by one or more processors, facilitates operation of the electronic device according to a process. It may be a computer program product that includes one or more non-transitory machine-readable media that encode.

(Exemplary method for determining vehicle position according to a light-based reference pattern)

  FIG. 5 is a flowchart of an exemplary method 500 for determining a position within an area according to one embodiment of the present disclosure. Method 500 includes receiving 504 an image of an asymmetric reference pattern displayed by a luminaire in the area. As described above, the vehicle includes a sensor configured to process an image of a light-based asymmetric reference pattern displayed by the luminaire. When the luminaire enters the FOV of a sensor located in the vehicle, the sensor receives an image of the asymmetric reference pattern and transmits the image to a processor operably coupled thereto. The processor is then configured to analyze the asymmetric reference pattern to determine the relative position of the vehicle from the luminaire. Thus, the system is configured to determine the exact vehicle position within the area from the received image of the asymmetric reference pattern, as will be further described.

  In some embodiments, accuracy and accuracy are improved by incorporating multiple sensors such that each sensor receives or otherwise processes an image of a given luminaire. Improvements include sensors where the vehicle position has a different FOV relative to the luminaire (eg, sensor # 1 where the vehicle to luminaire is at a 45 degree position, sensor # 2 where the vehicle to luminaire is at a 60 degree position, etc.) Is determined by using the image of the luminaire received. Data from multiple images are combined or integrated using techniques such as data fusion to determine a more accurate vehicle position within the area. In some embodiments, implementing multiple sensors is impractical due to system constraints (eg, vehicle size or overall system cost). In such embodiments, a single high resolution sensor can be used to improve system accuracy. Many other embodiments for improving the accuracy of the system will be apparent in light of this disclosure.

  In some other embodiments, accuracy and precision are improved by adjusting one or more attributes of the sensor rather than increasing the number and / or type of sensors used in the system. Sensor attributes such as shutter speed can be adjusted to minimize adverse effects on the received image due to external factors such as sensor movement and / or the level of ambient light present in the area. Shutter speed or exposure time is the length of time that the digital sensor is exposed to light. The amount of light reaching the sensor is proportional to the exposure time. These factors can reduce the clarity of the image and can reduce the accuracy of the determined vehicle position because the reference pattern appears distorted in the image. In order to reduce (or eliminate) an error caused by an external factor, image quality is improved and a clear image of a reference pattern is obtained by changing the exposure time of the sensor by adjusting the increase or decrease of the shutter speed. In the exemplary embodiment, sensors are placed on a vehicle that moves within an area. When the shutter speed of the sensor is slow and the exposure time is long, the image recorded by the sensor may become unclear (for example, a blurred image). Before the sensor receives and processes enough light to produce an image, the image appears blurry because the vehicle leaves the luminaire. Conversely, increasing the shutter speed of the sensor allows the sensor to process a sufficient amount of light and record a clear image before the vehicle moves the sensor out of the luminaire. A shutter speed such as 30-500 microseconds (μsec) is sufficient to capture a decoded image of a luminaire in a moving vehicle.

  Method 500 further includes determining 508 the coordinate position of the luminaire based on the received image of the asymmetric reference pattern displayed by the luminaire. Once displayed, the reference pattern can be decoded, eg, by relating a light source with a low light intensity to “0” and a light source with a high light intensity to “1” to obtain luminaire position data (eg, a luminaire identifier). ) To determine the vehicle position within the area. In an exemplary embodiment, the asymmetric light-based reference pattern is decoded using the reference pattern sequence such that the first bit (eg, the first light source) is located in the upper right corner of the luminaire. The sequence then follows, for example, a top-to-bottom and right-to-left order to determine the luminaire identifier. The luminaire identifier is a number or symbol associated with a particular location within the area, for example, the coordinate position of the luminaire. In addition to the reference pattern sequence, the reference pattern can be decoded using an algorithm such as a histogram-threshold algorithm. More particularly, the histogram-threshold determination algorithm sorts the pixels of the received image based on the light intensity level of the pixels to determine a reference pattern transmitted by the lighting device. This is illustrated in FIGS. 6A-6B, where the luminaire 100 has several light sources 604 (indicated by hatched boxes) that operate at a lower light intensity level than the other light sources 608. . In response to receiving the image, the system analyzes the image to determine a threshold value, which in turn includes values such as “0” and “1” in binary format for the bits of information ( For example, it can be used to assign to a pixel corresponding to a light source to obtain a message (eg, 01011011 in binary format). Each pixel is analyzed to determine the brightness level. In some embodiments, the exposure time of the sensor is very short (eg, 50 μsec) so that pixels of the image that do not correspond to a light source such as ambient light have very low light intensity values and appear dark from the image. It should be noted. On the other hand, the pixel associated with the light source has a higher light intensity value and appears bright in the image, so it can be easily distinguished from the pixel corresponding to the ambient light. The pixels of the image are counted to determine the number of pixels for each light intensity level. This is shown in FIG. 6B, where pixels corresponding to light sources 604 and 608 are counted and identified by luminance level. As shown, the count 612 corresponds to the pixel of the image associated with the lower light intensity light source 604 (indicated by the shaded box). On the other hand, the count 616 corresponds to a pixel of the light source 608 at a high light intensity level (indicated by a box without a shadow). As shown, count 616 is located further from zero along the light intensity level axis than count 612. The system is configured to determine a threshold 620 based on the pixel counts 612 and 616. In the exemplary embodiment, threshold 620 is used to distinguish between pixels associated with a low intensity level light source (eg, 604) and pixels of a high intensity level light source (eg, 608) for the purpose of decoding the reference pattern. The light intensity level value. As shown, threshold 620 is located at a light intensity value that is greater than count 612 but less than count 616. Once the threshold 620 is determined, the image can be analyzed using the threshold 620, with the pixel corresponding to the light source 604 at a low light intensity level (eg, “0”) and the pixel corresponding to the light source 608 at a high light intensity. It can be assigned to a level (eg, “1”). In other embodiments, for the purpose of decoding the reference pattern, the light color level can be used to sort or otherwise distinguish the pixels of the received image. Once assigned, the pixels corresponding to the light sources 604 and 608 are analyzed to determine a reference pattern and extract the pattern encoded information (eg, binary message).

  Once the luminaire position data is received and processed, the system is configured to determine the position of the luminaire in the received image. In an exemplary embodiment, the luminaire position data is combined with luminaire layout information to determine the position of the luminaire shown in the image. The luminaire layout information can include, for example, a map, look-up table, or database content that identifies or otherwise indicates the location of the luminaire within the area. In some embodiments, the map is a virtual representation of an area for determining the position of the vehicle based on luminaire identifiers such as numbers, symbols, or text. Other embodiments for determining the coordinate position of a luminaire within an area will be apparent in light of this disclosure.

  Method 500 further includes determining 512 the vehicle orientation relative to the area based on the orientation of the received image asymmetric reference pattern. As described above, the luminaire is configured to display an asymmetric light-based reference pattern. The asymmetric shape of the reference pattern allows the system to communicate both lighting fixture orientation and position information through the pattern. Thus, the received image contains both the orientation and position information of the luminaire in one image. The system is configured to analyze the received image to determine the orientation of the vehicle with respect to the area. In the exemplary embodiment, the system is configured to place a light source that indicates orientation relative to the area in the image, such as infrared light source 320 shown in FIG. 3C. The system, in some embodiments, may determine the position of such light sources based on the distance between the light sources (e.g., light sources that indicate orientation are located closer to each other than other light sources). it can. The system is further configured to associate a particular direction (eg, north) with respect to the area with the light source indicating the direction. In some embodiments, the orientation is entered programmatically, eg, the light source indicating the orientation is in the north direction. Using a light source that indicates the determined direction and its associated direction, the system is configured to analyze the recorded image to determine the orientation of the vehicle relative to the area. The vehicle orientation can also be used to convert the position of the vehicle relative to the luminaire to the position of the vehicle relative to the area, as will be further described. Other methods of determining vehicle orientation relative to the area will be apparent in light of this disclosure.

  Method 500 includes determining 516 the position of the vehicle relative to the luminaire based at least in part on the determined coordinate position of the luminaire. When the vehicle is located in a predetermined lighting fixture (for example, directly below it), the vehicle position and the lighting fixture position are the same. Accordingly, calculating the position of the vehicle is accomplished by determining the position of the luminaire as described above. However, a vehicle moving in the area is rarely positioned directly below the lighting fixture. More often, the vehicle is placed adjacent to and below the luminaire. Therefore, the vehicle is disposed at a position relatively away from the lighting fixture. The location of the luminaire can provide an approximate or estimated location of the vehicle in the area, but in an industrial environment such as a warehouse, in order to properly move goods, equipment and / or personnel across the area Accurate vehicle positioning is required. It is not sufficient to determine the position of the luminaire in order to calculate the exact position of the vehicle in the area. The system is further configured to determine a position of the vehicle relative to the luminaire.

  In an exemplary embodiment, the system uses a model that describes a mathematical relationship between the coordinates of a three-dimensional point representing the position of the luminaire and the coordinates of a two-dimensional projection point on the image plane. From which the relative position of the vehicle is determined. Using this model, the system can convert the known three-dimensional coordinate position of the luminaire to the three-dimensional coordinate position of a sensor located in the vehicle based on the received image of the luminaire.

FIG. 7 shows a model 700, such as a pinhole camera model, for determining the relative position of the vehicle from the luminaire shown in the received image, according to an exemplary embodiment of the present disclosure. Model 700 includes a sensor coordinate system 704 representing a reference axis from which sensor points 708 are located. The sensor point 708 is a coordinate position (for example, (x _s , y _s , z _s )) representing the position of a sensor disposed on the vehicle when an image is received. Therefore, the coordinate position of the sensor point 708 is the relative position of the vehicle from the lighting fixture. For the purpose of determining the two-dimensional coordinate position (x _s , y _s ) of the vehicle in the area along the x and y coordinate planes shown in FIG. 1B, the value of z _s is not treated as part of the analysis. The coordinate values xs and ys of the sensor point 708 are determined based on the coordinate position (for example, (x, y)) of the lighting fixture. The luminaire is represented by a luminaire point 712 located at a coordinate position (x ₁ , y ₁ , z ₁ ) with respect to the luminaire coordinate system 716. The luminaire point 712 represents the position of the luminaire in the area, so its coordinate position is known based on the received luminaire position data.

Image plane 720 is located between coordinate systems 704 and 716, and center 724 of plane 720 intersects optical axis 728. The optical axis 728 represents the distance from the lighting fixture in the area to the vehicle (for example, the distance Z shown in FIG. 2A). The image plane 720 is configured to identify a two-dimensional coordinate position (eg, (u, v)) represented as a projection point 722, and the projection point 722 is the coordinate position (eg, (x, y )). Projection point 722 is created using the coordinate values of luminaire point 712 along with projection line 732. The mathematical modeling for converting the three-dimensional coordinate position of the luminaire point 712 to the two-dimensional coordinate position (x, y) of the sensor point 708 is summarized as follows.

The vector Pc represents the coordinates of the projection point 722 on the image plane 720 expressed in units of pixels in the image plane coordinate system. The matrix A is a sensor matrix having unique parameters. The center 724 is represented by (c _x , c _y ) in Expression 2. Focal length f _x and f _y are also expressed in pixels. The vector P represents the coordinates of the luminaire point 712 having known values for X, Y and Z, as previously described. The matrix R | t represents rotational and translation parameters, called sensor extrinsic parameters, which take into account sensors and sensors around the motion of a static scene or object (eg luminaire) Describe the behavior. Note that the matrix R | t transforms the three-dimensional coordinate position (x, y, z) of the luminaire point 712 into a two-dimensional coordinate position (eg, (u, v)) in the image plane 720. . Image plane 720 is at a fixed distance relative to sensor point 708. When the distance of the optical axis 728 between the sensor point 708 and the luminaire point 712 is equal to zero, the above equation (2) becomes:

Using equation (6), the coordinate position of the sensor (x, y, z) can be determined as the coordinate position of the luminaire point 712. It should be noted that the above transformation does not take into account inaccuracies caused by eccentricity, thin prisms, and / or radial distortion. Such distortion occurs when there is a lens misalignment and / or defect for the sensor of the image capture device. Taking these factors into account, the total effective distortion can be modeled as follows.

  The parameters k, p and s are the coefficients of radial distortion, tangential distortion and thin prism distortion, respectively. These coefficients can in some embodiments be estimated using a sensor calibration procedure such as a two-dimensional calibration method. In an exemplary embodiment, the two-dimensional calibration method includes calculating eigenparameters (eg, matrix A) and distortion factors (eg, k, p, and s) from a series of images that include a known two-dimensional pattern. . These images can contain 3D to 2D data so that sensor parameters can be estimated. Once the intrinsic parameters and distortion factors of the sensor are determined, these values can be used to estimate the matrices R and t, which are then used to estimate the position of the sensor relative to the image plane 720 (eg, Used to determine point 708) in FIG.

  In some embodiments where a group of luminaires are implemented to form a two-dimensional pattern (eg, a reference pattern), the sensor is configured with a very short exposure time so that most of the area of the image appears dark. So that the luminaire (or its individual light source) present in the image is easily recognizable. As a result, fewer pixels have an associated light intensity, so less processing power is required to analyze the captured two-dimensional image to determine the reference pattern. Furthermore, since the sensor can capture an image with a short exposure time before the vehicle moves out of the field of view of the luminaire, errors due to motion blur are reduced.

(Further consideration)

  Many other configurations will be apparent in light of this disclosure. For example, in some embodiments of the present disclosure, the luminaire includes a sensor, such as an accelerometer, to reduce and / or eliminate vehicle positioning errors. In some applications, the luminaire may move relative to the floor despite being fixed to the building structure. Pendant luminaires pose particular challenges because they tend to swing and / or vibrate due to external factors such as, for example, air flow through the area. Movement of the luminaire can cause positioning errors because the received image shows the luminaire at a location other than the known coordinate position. As a result, the model for determining the relative position of the vehicle from the luminaire becomes inaccurate. In order to prevent such errors, the luminaire can include a sensor configured to measure the stability and relative motion of the luminaire. In exemplary embodiments, sensors such as accelerometers and gyroscopes are configured to measure the movement of the luminaire. These measurements can be transmitted to a remote computing system and / or vehicle via a wired or wireless network. Using these measurements, the system can update the luminaire position information and / or modify the relative position calculation. The vehicle is configured in some embodiments to update and / or modify information without additional commands and / or commands from the network. However, in other embodiments, the updated luminaire position information is performed by a central processor, such as a server or a remote computing system, although modifications to the relative position calculation may be performed locally by the vehicle. Many other embodiments will be apparent in light of this disclosure.

  FIG. 8 illustrates a bottom view of a luminaire that includes a light source for creating an asymmetric reference pattern of varying light intensity in an exemplary embodiment of the present disclosure. As seen in FIG. 8, the lighting fixture 800 includes a housing 802 having a plurality of visible light sources 804 and infrared light sources 808. A visible light source 804, such as an LED, is configured to emit visible light to illuminate an area below and / or around the lighting fixture 800. Infrared light source 808 is configured to generate infrared light and is operably coupled to light pipe 812. The light pipe 812 is then configured to display an asymmetric reference pattern using light received from the infrared light source 808. The displayed asymmetric reference pattern communicates luminaire position data to passing vehicles in the area.

  In the exemplary embodiment, light pipe 812 is a device such as a tube or pipe configured to receive light from infrared light source 808 and transmit the received light along the length of pipe 812. Note that due to the propagation of light through pipe 812, the portion of pipe 812 that is closest to infrared light source 808 is illuminated at a higher light intensity level than the portion of pipe 812 that is located at the opposite end of pipe 812. Should. In the exemplary embodiment, light pipe 812 is fabricated from a polymer material and pattern 816 is engraved. The engraving process is an automated process that provides the luminaire identifier in the form of a one-dimensional (1-D) pattern, depending on the application. However, more sophisticated manufacturing processes can create the pattern 816 in the form of a two-dimensional pattern. When illuminated, the pattern 816 displays an asymmetric reference pattern similar to a barcode that can be received by the image capture device.

  In some embodiments, the position of the light pipe 812 indicates the orientation of the luminaire relative to the area. In the exemplary embodiment, the side 820 of the luminaire 800 immediately adjacent to the light pipe 820 is understood to be in a particular direction (eg, north). In response, the system is configured to analyze the recorded image and determine the orientation of the vehicle relative to the area based on the position of the light pipe 812 as shown in the received image.

FIG. 9 illustrates a luminaire 900 configured in accordance with an exemplary embodiment of the present disclosure. The luminaire 900 is configured to accept a light source 912, eg, an infrared LED, in a number of configurations, and such luminaire 900 is configured to use the light source 912 to display a unique asymmetric reference pattern. The As seen in FIG. 9, the luminaire 900 has a housing 904 that includes a mount 908, eg, a solder pad, configured to receive the light source 912. During manufacture of a luminaire, a machine, such as a pick-and-place machine, assembles each luminaire 900 with a different arrangement of light sources 912, and thus luminaire position data (eg, illuminator position data (eg, Embed lighting fixture identifier). Using computer vision technology, the system is configured to decode luminaire position data from the placement of light sources 912 within luminaire 900. It should be noted that the number of available light source patterns depends on the particular configuration of the luminaire 900. The lighting fixture 900 includes, for example, three light source patterns. If each light source 912 is attached to the mount 908 at 10 different locations along the mount 908 or otherwise fixed, the number of different reference patterns is 1000 (10 ³ ). Furthermore, it should be noted that the luminaire 900 includes a reference light source 916. Reference light source 916 allows the system to decode the reference pattern displayed by light source 912 by providing a reference for determining the orientation of luminaire 900.

  In other embodiments of the present disclosure, the luminaire is configured to perform spatial dimension multiplexing visible light communication (SDMVLC). In an exemplary embodiment, the luminaire is comprised of multiple light sources, such as infrared or visible light sources, that transmit data frames (eg, different reference patterns) sequentially in a temporal sequence. A temporal sequence is a series of different reference patterns that are transmitted in a batch (eg, display pattern 1, pattern 2, next pattern 3, and then repeat). Each reference pattern includes at least one bit of data as described above. Thus, multiple patterns can transmit a stream of information that can be decoded by the system. The duration of the temporal sequence is to allow the image capture device to record all the reference patterns displayed from the lighting device as defined by the data transmission protocol. Thus, the temporal sequence is transmitted at a specific frame rate. For example, the temporal sequence is transmitted at a frame rate that is lower than the maximum frame rate of an image capture device, such as a camera or sensor, in some embodiments. However, if the temporal sequence frame rate is too low, the light source may flicker and adversely affect the surrounding lighting and aesthetics. A frame rate of, for example, 80 hertz (Hz) for the temporal sequence is acceptable for an image capture device having a frame rate of 240 frames / second. In such an example, the image capture device records and / or processes three images of each reference pattern (ie, frame). Thus, no matter when the device starts recording, the device captures at least one image of each displayed reference pattern, so synchronization between the luminaire and the image capture device is not necessary.

  Different reference patterns are generated and displayed using light sources configured to vary light intensity levels individually and dynamically. Thus, each light source is a single channel or source of information / data. As a result, the luminaire transmits information for each individual light source rather than a group of light sources, increasing the amount of information transmitted by the luminaire. By increasing the number of reference patterns displayed by the luminaire, the patterns can be displayed at a lower frequency and at the same time provide high data processing capabilities. As a result, less complex components can be implemented to transmit the reference pattern at low frequencies (eg, there is no driver to modulate the light source at high frequencies), thus reducing the complexity of the luminaire. .

  The system, in some embodiments, is configured to generate a high resolution image that allows processing of a reference pattern displayed at a low light intensity level. In an exemplary embodiment, the light source of the luminaire is operated at a high light intensity level, eg, 100% light intensity level, to receive a high resolution image. The system is then configured to analyze the high resolution image to find individual luminaire light source pixels in the image. Upon receiving the high resolution image, the luminaire is configured to transmit a light based reference pattern at a lower light intensity level. In response, the received image is analyzed using pixel locations identified from the high resolution image to determine a reference pattern. Thus, the illuminator consumes less energy to generate an asymmetric light-based reference pattern, thus improving system efficiency.

  In other embodiments of the present disclosure, the luminaire is comprised of an image capture device such as a camera or a dynamic vision sensor. The vehicle includes a light source configured to display an asymmetric light-based reference pattern disposed thereon. The position of the vehicle is determined by the processor of the image capture device using the methods and techniques described herein. Once determined, the position of the vehicle within the area is transmitted to the vehicle via a network such as BLUETOOTH®, ZIGBEE® and Wi-Fi network. Processing the vehicle and luminaire position data in this manner reduces the computational complexity of the system's vehicle.

(VLC mobile transport vehicle identification)

  In addition to using a light-based communication signal in the form of an asymmetric reference pattern, some embodiments of the present disclosure use VLC signals to determine the position of the vehicle within the area. A luminaire can generate a VLC signal by modulating one or more light sources disposed therein. In order to accurately determine the vehicle position using the VLC signal, the luminaire is placed at a certain distance from a sensor located on the vehicle. Further, in order to improve the accuracy of the system, the sensor can be placed on the vehicle such that the sensor does not tilt relative to the vehicle (eg, does not move in the direction of pitching, yawing or rolling) during movement of the vehicle. The known distance allows the system to associate a pair of angles with each pixel location in the image received by the sensor. This angle is used to determine the position of the vehicle relative to the luminaire depicted in the image, as will be described in more detail. Further, to determine the orientation of the vehicle relative to the area, the system processes multiple images of the luminaires in the area to determine the location of the luminaires and the relative vehicle distance therefrom. Configured.

(System structure and operation)

  FIG. 10 is a block diagram illustrating an example of an optical-based communication (LCom) system 1000 configured in accordance with an embodiment of the present disclosure. As shown, system 1000 can include one or more LCom-enabled luminaires 1100 configured for light-based communication connection with a receiver of vehicle 90 via an LCom signal. As disclosed herein, such an LCom may be provided by a visible light based signal, according to some embodiments. In some cases, LCom may be provided in only one direction. For example, the LCom data may be transmitted from a predetermined LCom-compatible luminaire 1100 (eg, transmitter) to a vehicle 90 (eg, a receiver) or from the vehicle 90 (eg, transmitter) to a predetermined LCom-compatible luminaire 1100 (eg, Receiver). In some other cases, the LCom may be provided bi-directionally between a given LCom-enabled luminaire 1100 and the vehicle 90, where both function as transceiver devices that can transmit and receive.

  In some cases where system 1000 includes a plurality of LCom-enabled luminaires 1100, all (or a subset thereof) are configured to be communicatively coupled to each other to provide inter-luminaire communication. Also good. In one such scenario, for example, communication between luminaires may be used to notify another luminaire 1100 that a given vehicle 90 exists and to notify the location information of that particular vehicle 90. it can. However, such interluminaire communication is not essential, as will be understood in light of this disclosure.

  As can be further seen in this exemplary embodiment, the system 1000 allows for communication coupling with the network 3000 and one or more servers or other computer systems 3010. For example, a communication link can be provided as needed between the network 3000 and the vehicle 90 and / or one or more LCom-enabled luminaires 1100. Network 3000 may be a wireless local area network, a wired local network, or a combination of local wired and wireless networks, and may further include access to a wide area network such as the Internet or a campus wide network. In short, the network 3000 can be any communication network.

  Computer system 3010 is any suitable computing system capable of communicating via network 3000, such as a cloud-based server computer, and in some embodiments programmed or configured to provide LCom-related services. May be. For example, an LCom related service is one in which the computer system 3010 is configured to provide storage of luminaire location data. Many other such configurations will be apparent in light of this disclosure.

  FIG. 11A is a block diagram illustrating an LCom enabled lighting fixture 1100a configured in accordance with one embodiment of the present disclosure. FIG. 11B is a block diagram illustrating an LCom enabled lighting fixture 1100b configured in accordance with another embodiment of the present disclosure. As shown, the difference between the luminaire 1100a and the luminaire 1100b relates to the position of the controller 1150. For ease of consistency and understanding of the present disclosure, LCom-enabled luminaires 1100a and 1100b may hereinafter be collectively referred to as LCom-enabled luminaires 1100, except when referred to separately. Further, although various modules are shown as independent modules for purposes of illustration, it should be noted that any number of modules may be integrated with one or more other modules. For example, the controller 1150 can be integrated with the driver 1120. Similarly, processor 1140 and memory 1130 can be integrated within controller 1150. Many other configurations can be used.

  As shown, a given LCom-enabled luminaire 1100 may include one or more solid state light sources 1110 in some embodiments. The amount, density, and placement of the solid state light source 1110 utilized in a given LCom enabled luminaire 1100 can be customized as desired for a given target or end use application. A given solid state light source 1110 can include one or more solid state emitters, which are any of a wide variety of semiconductor light source devices, such as light emitting diodes (LEDs), organic light emitting diodes (OLEDs), A polymer light emitting diode (PLED), or any combination thereof. A given solid state emitter may be configured to emit electromagnetic radiation as desired for a given target application or end use, including, for example, the visible spectral band and / or infrared (IR) There are other parts of the electromagnetic spectrum that are not limited to spectral bands and / or ultraviolet (UV) spectral bands. In some embodiments, a given solid state emitter may be configured for emission of a single correlated color temperature (CCT) (eg, a white light emitting semiconductor light source). In other embodiments, a given solid state emitter may be configured for color tunable radiation. For example, in some cases, a given solid state emitter may be a multi-color (eg, two-color, three-color, etc.) semiconductor light source configured for a combination of radiation. For example: (1) red-green-blue (RGB); (2) red-green-blue-yellow (RGBY); (3) red-green-blue-white (RGBW); (4) dual white; and / or Or (5) any one or a combination thereof. In some cases, a given solid state emitter can be configured as a high intensity light source. In some embodiments, a given solid state emitter can comprise a combination of any one or more of the exemplary radiation functions described above. In any case, a given solid state emitter may be packaged or unpackaged as needed, and may be mounted on a printed circuit board (PCB) or other suitable intermediate / substrate. . In some cases, the power and / or control connections of a given solid state emitter can be routed from a given PCB to a driver 1120 (described below) and / or other devices / components as needed. Other suitable configurations for one or more solid emitters of a given solid state light source 1110 will depend on the given application and will be apparent in light of this disclosure.

A given solid state light source 1110 may also include one or more optical elements that are optically coupled to the one or more solid state emitters. According to some embodiments, the optical element of a given solid state light source 1110 has one or more specific wavelengths (eg, visible light, UV, infrared, etc.) of light emitted by a solid emitter optically coupled thereto. May be configured to emit. For this purpose, the optical element can include an optical structure (eg, window, lens, dome, etc.) formed from any of a wide variety of optical materials. For example, (1) a polymer such as poly (methyl methacrylate) (PMMA) or polycarbonate; (2) a ceramic such as sapphire (Al ₂ O ₃ ) or yttrium aluminum garnet (YAG); ) Glass; and / or (4) any one or more combinations thereof. In some cases, the optical elements of a given solid state light source 1110 may be formed from a single (eg, monolithic) piece of optical material to provide a single continuous optical structure. In some other cases, the optical elements of a given solid state light source 1110 may be formed from a plurality of pieces of optical material to provide a plurality of pieces of optical structure. In some cases, the optical elements of a given solid state light source 1110 can include optical features. For example: (1) anti-reflective (AR) coating, (2) reflector; (3) diffuser; (4) polarizer; (5) brightness enhancer; (6) phosphor material (eg, light received thereby) And / or (7) any one or more combinations thereof. In some embodiments, the optical elements of a given solid state light source 1110 can be configured, for example, to focus and / or collimate light transmitted therethrough. Other suitable types of optical systems, light transmission characteristics, and optical element configurations for a given solid state light source 1110 will depend on the given application and will be apparent in light of this disclosure.

  According to some embodiments, one or more solid state light sources 1110 of a given LCom enabled luminaire 1100 may be electronically coupled with a driver 1120. In some cases, the driver 1120 is an electronic driver (eg, single channel, multichannel) configured to be used, for example, in controlling one or more solid state emitters of a given solid state light source 1110. It may be. For example, in some embodiments, the driver 1120 can determine the on / off state, dimming level, emission color, correlated color temperature (CCT), and / or saturation of a given solid emitter (or emitter grouping). It can be configured to control. For such purposes, the driver 1120 can utilize a wide range of driving techniques, for example: (1) pulse-width modulation (PWM) dimming protocol; (2) current dimming protocol. (3) Triode for alternating current (TRIAC) dimming protocol; (4) Constant current reduction (CCR) dimming protocol; (5) Pulse-frequency modulation (pulse-frequency modulation) : PFM) dimming protocol; (6) Pulse-code modulation (PCM) dimming protocol; (7) Line voltage (main line) dimming protocol Tocol (eg, a dimmer is connected before the input of the driver 1120 to regulate the AC voltage to the driver 1120); and / or (8) any one or more combinations thereof. Other suitable configurations and lighting control / drive techniques for the driver 1120 will depend on the specific application and will be apparent in light of this disclosure.

  As will be appreciated in light of this disclosure, a given solid state light source 1110 may include or be operably coupled with other circuits / components that may be used, for example, in solid state lighting. For example, a given solid state light source 1110 (and / or host LCom-enabled luminaire 1100) can be configured to host or operably couple with any of a wide range of electronic components. For example, (1) a power conversion circuit (for example, an electric ballast circuit that converts an AC signal into a DC signal with a desired current and voltage to supply power to a predetermined solid-state light source 1110); (2) a constant current / voltage driver Components; (3) transmitter and / or receiver (eg, transceiver) components; and / or (4) local processing components. Where such components are included, these may be implemented in some embodiments, for example, on one or more driver 1120 boards.

  As can further be seen from FIGS. 11A-11B, a given LCom-enabled luminaire 1100 can include a memory 1130 and one or more processors 1140. The memory 1130 may be any suitable type (eg, RAM and / or ROM, or other suitable memory) and size, and in some cases, volatile memory, non-volatile memory, or combinations thereof. May be implemented. A given processor 1140 can typically be configured, and in some embodiments, for example, a given host LCom enabled luminaire 1100 and one or more thereof (eg, in memory 1130 or elsewhere). ) Can be configured to perform operations associated with application 1132; In some cases, memory 1130 may be utilized, for example, for a processor workspace (eg, one or more processors 1140) and / or temporarily or permanently host media, programs, applications, and / or content. It may be configured for storage in the LCom compliant lighting fixture 1100. In one exemplary embodiment, the memory 1130 may be a location (manually programmed or Or received using an embodiment of the present disclosure) and may further include a look-up table (LUT) or other storage device that indicates the luminaire position within the area.

  One or more applications 132 stored in the memory 1130 may be accessed and executed by one or more processors 1140 of a given LCom-enabled luminaire 1100, for example. According to some embodiments, a given application 1132 can be implemented by any suitable standard and / or custom / private programming language. For example: (1) C; (2) C ++; (3) Objective C; (4) JavaScript®; and / or (5) any other suitable custom or private instruction set. In a more general sense, application 1132 may be any suitable non-temporary that, when executed by one or more processors 1140, performs some or all of the functions of a given LCom-enabled luminaire 1100. It may be instructions encoded on a static machine readable medium. In any case, the luminaire can deliver the luminaire location to the passing vehicle 90 using the VLC signal.

  According to some embodiments, one or more solid state light sources 1110 of a given LCom enabled luminaire 1100 may output light (eg, LCom signal) encoded with, for example, light and / or LCom data. It can be controlled electronically. To that end, a given LCom enabled luminaire 1100 may include one or more controllers 1150 or may be communicatively coupled. In some such exemplary embodiments shown in FIG. 11A, the controller 1150 is hosted by a given LCom enabled luminaire 1100 and one or more solid state light sources 1110 (1-N ) And (eg, via a communication bus / interconnect). In this example, the controller 1150 can output a digital control signal to any one or more of the solid state light sources 1110, eg, a predetermined local source (eg, on-board memory 1130) and / or a remote source ( For example, based on wired and / or wireless input received from a control interface or network 3000). As a result, a given LCom-enabled luminaire 1100 can have any number of output beams (which can include light and / or LCom data (eg, LCom signals) as desired for a given target or end use application. 1-N) can be controlled to output. However, the present disclosure is not limited thereto.

  For example, in some other embodiments as shown in FIG. 11B, the controller 1150 may be partially or fully packaged by a predetermined solid state light source 1110 of a predetermined LCom enabled luminaire 1100 or otherwise. And can be operably coupled (eg, via a communication bus / interconnect) with one or more solid state light sources 1110. If the LCom-enabled luminaire 1100 includes a plurality of solid state light sources 1110 that host its own controller 1150, each such controller 1150, in a sense, distributes the distributed controller 1150 to the LCom-enabled luminaire 1100. It can be thought of as a mini-controller. In some embodiments, the controller 1150 may be implemented on one or more PCBs of the host solid state light source 1110, for example. In this example, the controller 1150 can output a digital control signal to the associated solid state light source 1110 of the LCom enabled luminaire 1100, which can be, for example, a predetermined local source (eg, onboard memory 1130, etc.) and This may be done based on wired and / or wireless input received from a remote source (eg, control interface, network 3000, etc.). As a result, the LCom-enabled luminaire 1100 can have any number of output beams (1− that can contain light and / or LCom data (eg, LCom signals) as desired for a given target or end use application. N) can be controlled to output.

  According to some embodiments, the predetermined controller 1150 hosts one or more lighting control modules, for example, to adjust the operation of the solid state emitter of the predetermined solid state light source 1110 according to the position communication of the luminaire. Can be programmed or configured to output one or more control signals. For example, the predetermined controller 1150 may be configured to output a control signal that controls whether the light beam of a predetermined solid state emitter is on / off. In some examples, the predetermined controller 1150 may be configured to output a control signal for controlling the intensity / brightness (eg, darker; brighter) of light emitted by the predetermined solid state emitter. In some cases, the predetermined controller 1150 may be configured to output a control signal for controlling the color (eg, mixing; tuning) of the light emitted by the predetermined solid state emitter. Thus, if a given solid state light source 1110 includes two or more solid state emitters configured to emit light having different wavelengths, the control signal adjusts the relative luminance of the different solid state emitters to determine that solid state light source. The mixed color output by 1110 is changed. In some embodiments, the controller 1150 is configured to output a control signal to an encoder 1172 (described below) to facilitate encoding of LCom data for transmission by a given LCom enabled luminaire 1100. be able to. In some embodiments, the controller 1150 is configured to output a control signal to a modulator 1174 (described below) to facilitate modulation of the LCom signal for transmission by a given LCom-enabled luminaire 1100. can do. Other suitable configurations and control signal outputs for a given controller 1150 for a given LCom-enabled luminaire 1100 will depend on the given application and will be apparent in light of this disclosure.

  According to some embodiments, a given LCom enabled luminaire 1100 may include an encoder 1172. In some embodiments, the encoder 1172 may be configured to encode LCom data in preparation for transmission by the host LCom enabled lighting fixture 1100, for example. For this purpose, encoder 1172 may be provided with any suitable configuration, as will be apparent in light of this disclosure.

  According to some embodiments, a given LCom enabled luminaire 1100 can include a modulator 1174. In some embodiments, the modulator 1174 may be configured to modulate the LCom signal, eg, in preparation for transmission of the LCom signal by the host LCom enabled luminaire 1100. In some embodiments, the modulator 1174 is a single channel or multiple channel electronic driver configured to be used, for example, to control the output of one or more solid state emitters of a given solid state light source 1110. (For example, the driver 1120) may be used. In some embodiments, the modulator 1174 controls the on / off state, dimming level, color development, correlated color temperature (CCT), and / or saturation of a given solid state emitter (or group of emitters). May be configured. For this purpose, the modulator 1174 can use a wide range of driving techniques, for example: (1) pulse-width modulation (PWM) dimming protocol, (2) current dimming protocol. (3) Triode for alternating current (TRIAC) dimming protocol; (4) Constant current reduction (CCR) dimming protocol; (5) Pulse-frequency modulation (pulse-frequency modulation) : PFM) dimming protocol; (6) Pulse-code modulation (PCM) dimming protocol; (7) Line voltage (main line) dimming protocol (Eg, a dimmer is connected before the input of the modulator 1174 to regulate the AC voltage to the modulator 1174); and / or (8) any other lighting control / Driving technology. Other suitable configurations and lighting control / drive techniques for modulator 1174 will depend on the specific application and will be apparent in light of this disclosure.

  According to some embodiments, a given LCom enabled luminaire 1100 can include a multiplier 1176. Multiplier 1176 can typically be configured, and in some embodiments can be configured to combine the input received from upstream modulator 1174 and the input received from ambient light sensor 1165 ( Explained below). In some cases, multiplier 1176 may be configured to increase and / or decrease the amplitude of the passing signal as needed. Other suitable configurations for multiplier 1176 will depend on the specific application and will be apparent in light of this disclosure. According to some embodiments, a given LCom enabled luminaire 1100 can include an adder 1178. Adder 1178 can typically be configured, and in some embodiments can be configured to combine the input received from upstream multiplier 1176 with the DC level input. In some examples, summer 1178 can be configured to increase and / or decrease the amplitude of the passing signal as needed. Other suitable configurations for summer 1178 will depend on the specific application and will be apparent in light of this disclosure.

  According to some embodiments, a given LCom enabled luminaire 1100 may include a digital to analog converter (DAC) 1180. The DAC 1180 can typically be configured and in some embodiments converts the digital control signal into an analog control signal that is applied to a predetermined solid state light source 1110 of the host LCom enabled luminaire 1100 and from there LCOM It can be configured to output a signal. It should be noted that in some embodiments, the DAC 1180 can be further integrated into the controller 1150. Other suitable configurations will be apparent in light of this disclosure.

  According to some embodiments, a given LCom enabled luminaire 1100 may include one or more sensors 1160. In some embodiments, a given LCom enabled luminaire 1100 can optionally include an altimeter 1161. If an altimeter 1161 is included, it can typically be configured, and in some embodiments, the altitude of the host LCom-enabled luminaire 1100 relative to a predetermined fixed level (eg, floor, wall, ground, or other surface). It may be configured to assist in the determination. In some embodiments, a given LCom enabled luminaire 1100 can optionally include a geomagnetic sensor 1163. If a geomagnetic sensor 1163 is included, it can typically be configured, and in some embodiments, the orientation of the host LCom enabled luminaire 1100 with respect to a geomagnetic pole (eg, geomagnetic north) or other desired orientation and / or It may be configured to determine movement and the desired orientation may be customized as desired for a given target application or end use. In some embodiments, a given LCom enabled luminaire 1100 can optionally include an ambient light sensor 1165. If ambient light sensor 1165 is included, it can typically be configured and in some embodiments may be configured to detect and measure ambient light levels in the ambient environment of host LCom enabled luminaire 1100. . In some cases, ambient light sensor 1165 may be configured to output a signal to multiplier 1176 of LCom enabled luminaire 1100, for example. In some embodiments, a given LCom enabled luminaire 1100 can optionally include a gyroscope sensor 1167. If a gyroscope sensor 1167 is included, it can typically be configured, and in some embodiments, to determine the orientation (eg, rolling, pitching, and / or yawing) of the host LCom enabled luminaire 1100. It may be configured. In some embodiments, a given LCom enabled luminaire 1100 can optionally include an accelerometer 1169. Where an accelerometer 1169 is included, it can typically be configured and in some embodiments may be configured to detect movement of the host LCom enabled luminaire 1100. In any event, the predetermined sensor 1160 of the predetermined host LCom enabled luminaire 1100 may include mechanical and / or solid components as desired for a predetermined target or end use application. It should also be noted that the present disclosure is not limited only to these exemplary optional sensors 1160. In some other embodiments, additional and / or different sensors 1160 may be provided as desired for a given target or end use application. Alternatively, the sensor 1160 may not be provided. Many configurations are apparent in light of this disclosure.

  According to some embodiments, a given LCom-enabled luminaire 1100 can include a communication module 1170 that can be wired (eg, Universal Serial Bus or USB, Ethernet (registered), as needed. Trademark), firewire, etc.) and / or wireless (eg, Wi-Fi, Bluetooth, etc.) communications. According to some embodiments, the communication module 1170 may be a transceiver or other network interface configured to communicate locally and / or remotely using any of a wide range of wired and / or wireless communication protocols. It may be a circuit. As a wireless communication protocol, for example, (1) digital multiplexer (DMX) interface protocol; (2) Wi-Fi protocol; (3) Bluetooth (registered trademark) protocol; (4) DALI (digital addressable interface) protocol (5) ZigBee protocol; and / or (6) any one or more combinations thereof. However, the present disclosure is not limited to only these exemplary communication protocols, and according to some embodiments, in a more general sense, any suitable communication protocol, wired and / or wireless, standard and / or Or, custom / private, may be utilized by the communication module 1170 as desired for a given target application or end use. In some cases, the communication module 1170 can be configured to facilitate inter-luminaire communication between LCom compliant luminaires 1100. Additionally or alternatively, the communication module 1170 can be configured to allow reception of information from the network 3000, such as luminaire location data. Regardless of whether the luminaire position data is stored in the luminaire or received from somewhere else, the luminaire position data is used to generate an LCom signal that is emitted by the luminaire 1100. The position of the luminaire can be communicated to the passing vehicle 90. The communication module 1170 may use any suitable wired and / or wireless transmission technology (eg, radio frequency or RF, transmission, infrared, or IR, light modulation, etc.) as desired for a given target or end use application. It may be configured to be used. These transmission techniques may be implemented with a transceiver integrated with or connected to the communication module 1170, such as a Bluetooth® beacon. Other suitable configurations for the communication module 1170 will depend on the specific application and will be apparent in light of this disclosure.

As described above, a given LCom enabled luminaire 1100 may be configured to output light and / or light encoded with LCom data (eg, an LCom signal) in accordance with some embodiments. FIG. 12 illustrates an exemplary arbitrary LCom signal that may be transmitted by an LCom enabled luminaire 1100 according to one embodiment of the present disclosure. As illustrated, the LCom enabled lighting fixture 1100 may be configured to transmit a predetermined LCom signal over a predetermined time interval (t ₁ -t ₀ ). In some cases, a given LCom enabled luminaire 1100 may be configured to repeatedly output the one or more LCom signals.

  Network 3000 may be any suitable public and / or private communication network. For example, in some cases, the network 3000 may be a local area network (LAN) operably coupled to a wide area network (WAN) such as the Internet. In some cases, the network 3000 may include one or more second generation (2G), third generation (3G), and / or fourth generation (4G) mobile communication technologies. In some cases, network 3000 may include a wireless local area network (WLAN) (eg, Wi-Fi wireless data communication technology). In some cases, network 3000 may include Bluetooth wireless data communication technology. In some cases, network 3000 may support infrastructure and / or functions such as servers and service providers (eg, computer system 3010), but such functions may communicate over network 3000. Not required. In some examples, the vehicle 90 may be configured for communication connection with, for example, the network 3000 and one or more LCom-enabled luminaires 1100. In some cases, the vehicle 90 is configured to receive data from the network 300, which serves to supplement the LCom data received by the vehicle 90 from the LCom enabled luminaire. In some cases, vehicle 90 may receive data (eg, known reference location information, luminaire location, luminaire identifier, and / or predetermined) from network 3000 that facilitates navigation through one or more LCom compliant luminaires 1100. For example, other data relating to the LCom-enabled luminaire 1100). Many configurations of the network 3000 are apparent in light of this disclosure.

  FIG. 13A illustrates an exemplary LCom system that includes an LCom-enabled luminaire and a vehicle in one embodiment of the present disclosure. As shown, this example scenario includes two luminaires 1100 that each communicate with a vehicle 90 running an LCom-based navigation application. The navigation application can be, for example, one of the applications stored in the memory 220 and executed by the processor 216. As shown, the LCom signal being communicated generally includes data 1300 that includes location information, which can be used for navigation. For example, if the user is receiving light from a particular luminaire 1100 with a known location, the navigation application knows where the user is and can continue to guide the user along the target path. .

  Data 1300, such as location information transmitted by luminaire 1100, can take any number of forms. For example, in some embodiments, the location of the luminaire is as a relative position (eg, relative to another luminaire 1100 or some other object having a known location) and / or (eg, on a grid-based map) (XY coordinates) can be communicated as an absolute position. In still other embodiments, the location of the luminaire may be communicated as an environment ID, and the transmitted ID is converted to a specific location on a predetermined map of the environment being navigated. In such an exemplary case, for example, the luminaire may use dual tone multi frequency (DTMF) encoding, which means that it transmits two singular frequencies in succession. To do.

  FIG. 13B shows how an exemplary DTMF-based ID system works. As will be appreciated, the predetermined environment 271 is the area to be navigated and has several LCom-enabled luminaires 101. The environment 271 may be, for example, a supermarket or retail store, or a shopping mall, parking garage, or large office space, to name a few examples. The environment 271 is effectively divided into a grid of physical locations, each location being associated with at least one luminaire 1100. As can be further seen, each luminaire 1100 is associated with two distinct frequencies that can be transmitted periodically. Thus, two unique frequencies can be used to relate the location of that particular luminaire to a particular location in the environment. For example, if the user is receiving light from luminaire # 1 (which transmits 697 Hz and 1209 Hz in this exemplary embodiment), the navigation application “knows” that the user is in the northwest corner of environment 271. " Similarly, if the user is receiving light from luminaire # 12 (which transmits 941 Hz and 1477 Hz in this exemplary embodiment), the navigation application “knows” that the user is in the southeast corner of the environment, And so on. Thus, in an example scenario, assuming that the environment 271 is a store that sells some type of merchandise, each location can be associated with a particular product or range of products. Thus, according to some embodiments, a navigation application can guide a user to a predetermined product location. It should be noted that the entire frequency-based grid can be scaled to a higher or lower frequency and operates as described herein to specifically identify the position of individual luminaires 1100.

  FIG. 13C illustrates an exemplary method for transmitting location information from an LCom enabled luminaire in one embodiment of the present disclosure. As shown, the method includes a step 1301 of emitting light output by at least one solid state light source of the luminaire. The method further includes modulating 1303 the light output to emit an LCom signal, the LCom signal having data including position information indicative of a physical position of at least one light source. According to some embodiments, this position information can indicate the position of a particular luminaire directly by relative position information or absolute position information, as described above. In other embodiments, this location information can indirectly indicate the location of a particular luminaire by an environment ID that is translated to a particular location on a predetermined map of the environment being navigated. Many other embodiments and variations for using the location of a luminaire to navigate a given area will be apparent in light of this disclosure.

(Exemplary method of determining vehicle position using VLC signal)

  FIG. 14 is a flowchart of an exemplary method 1400 for determining the position of a vehicle within an area, in accordance with an embodiment of the present disclosure. The method 1400 includes receiving 1404 a first image of a first luminaire at a first location in the area, the first image including a first visible light communication signal from the first luminaire. A visible light communication (VLC) signal is a light-based signal emitted or otherwise emitted by modulating the light source of a luminaire. In an exemplary embodiment, the first luminaire transmits a VLC signal by modulating its light source to emit light at a lower light intensity level (eg, 95% of the maximum light intensity level). The VLC signal is encoded with a luminaire identifier, such as an identification number, that can be used to determine the location of a given luminaire within the area, as will be further described.

  As the vehicle passes through the area, a sensor located on the vehicle records or processes an image of the area in the sensor's FOV. An object such as a luminaire in the sensor's FOV is recorded and displayed by one or more pixels of the image. This is illustrated in FIG. 15, where image 1500 includes a luminaire 1504. In the image 1500, each pixel is represented by a pair of indices (u, v) in an image coordinate system 1508 (eg, uv coordinate system). In an exemplary embodiment, the vehicle includes a sensor such as a camera having a resolution of 640 × 480. For purposes of explanation, FIG. 15 shows an image 1500 having a 5 × 7 resolution, as indicated by grid lines 512. As a result, the pixels of the image 1500 are indexed with numbers 1 to 7 from left to right along the u direction of the image coordinate system 1508. Similarly, pixels of image 1500 are indexed with numbers 1 to 5 from top to bottom along the v direction of image coordinate system 1508. Thus, a particular pixel of image 1500 can be identified using a coordinate position (u, v) based on image coordinate system 1508, for example, the pixel representing the center of image 1500 is pixel (4, 3). . In some cases, the image 1500 may include a plurality of luminaires 1504 depending on the FOV and / or luminaire placement of the given sensor. Image 1500 also includes a VLC signal (indicated by the hatched box) for luminaire 1504, which will be decoded or processed to determine the location of the luminaire, as will be further described. Can do.

  Method 1400 further includes receiving 1408 a second image of a second luminaire at a second location in an area different from the first location, wherein the second image is a second visible light from the second luminaire. Includes communication signals. The second image of the second lighting fixture can be received in the same manner as the first received image. In some embodiments, the vehicle can move to another location within the area to receive the second image. The positions of the first and second lighting fixtures are located within the area so that the system can determine the orientation of the vehicle relative to the area based on the positions of the first and second lighting fixtures, as will be further described.

  Method 1400 further includes a step 1412 of determining a first position of the first luminaire in the area based on the first visible light communication signal shown in the first image. When the first image is received, the system is configured to determine the position of the first luminaire. In an exemplary embodiment, the system is configured to identify pixels in the first image corresponding to the first light fixture from other pixels corresponding to the background object, eg, a ceiling located on the floor. . In order to distinguish image pixels, the system, in the exemplary embodiment, is one of two ways: globally (eg, scanning the entire image) or locally (eg, of interest). An area or region) is configured to scan or analyze the first image. The first image is analyzed globally to allow the system to distinguish between pixels associated with the first luminaire and other pixels associated with the background object. The system is configured to identify pixels associated with the first luminaire based on pixel intensity values and thresholds. The pixel light intensity value is a numerical value indicating the light level of a predetermined pixel of the image. A threshold is a pixel intensity value that can be used to distinguish between pixels associated with a luminaire and pixels corresponding to a background object. In an exemplary embodiment, the threshold is a pixel intensity value that corresponds to a minimum light intensity value associated with a pixel of the first luminaire. Comparing the pixel intensity value of each pixel to a threshold, the system can identify a pixel of the first image corresponding to the first luminaire.

  Upon identifying the pixels of the first image of the first luminaire, the system is further configured to perform a local scan of those pixels to select the pixels representing the first luminaire. The image is further analyzed locally (eg, analyzing an area of interest) to determine luminaire location data (eg, luminaire identifier) from a subset of pixels of the received image. In an exemplary embodiment, the system is configured to analyze a subset of image pixels corresponding to the first luminaire. The subset of image pixels corresponds to a 2 × 8 pixel area of the image in some embodiments. The system is configured to scan a subset of image pixels at a frame exposure rate, eg, 8 kilohertz (KHz), to identify a luminaire identifier (eg, identification number) based on the light intensity value of the pixel. .

  Once identified, the luminaire identifier can be used to determine the position of the first luminaire within the area. In an exemplary embodiment, the luminaire identifier is combined with luminaire layout information, such as look-up tables, maps, and database content, locally (eg, in a vehicle memory) and / or globally (eg, computing). Stored in the system memory) to determine the coordinate position (eg, (x, y)) of the first luminaire. Many other configurations will be apparent in light of this disclosure.

  Method 1400 further includes a step 1416 of determining a second position of the second luminaire in the area based on the second visible light communication signal shown in the second image. In response to receiving the second image, the system is configured to determine a second position of the second luminaire in a manner similar to that previously described for the first luminaire. Next, the position of the luminaire determined as described herein can be used to determine (1) the orientation of the vehicle relative to the area and (2) the coordinate position of the vehicle within the area.

  Method 1400 includes determining 1420 a position of the vehicle relative to the area based on the determined first and second positions and at least one pixel of the first and second images. The system is configured to determine the coordinate position (eg, (x, y) coordinates) of the vehicle within the area. In an exemplary embodiment, the coordinate position is (1) a pixel of an image corresponding to a given luminaire, and (2) first and second angles associated with the pixel position in the image in which the pixel is included. To be determined. The pixel of the image corresponding to the luminaire can be selected in several ways. For example, in some embodiments, a pixel is selected that corresponds to a pixel location that represents the center of mass of the luminaire shown in the image. This is shown in FIG. 15 and the pixel located at the uv coordinate position (6, 4) is selected as the pixel corresponding to the center of mass of the luminaire 1504 shown in the image 1500. Other methods for selecting the pixel corresponding to the luminaire shown in the image include selecting the pixel having the maximum light intensity level in the luminaire shown in the image and / or the central pixel location in the luminaire. It may include selecting a pixel that is located. In a more general sense, any one of the pixels corresponding to the luminaire shown in the image can be used to determine the position of the vehicle relative to the luminaire.

  Once the pixel location of the selected pixel is identified, it is used to identify the first angle and the second angle. In general, pixels located at the same pixel location in different images can be associated with the same first and second angles relative to the image plane of the sensor. In the exemplary embodiment, the system is configured to associate a horizontal angle α and a vertical angle β with each pixel of the image. The system then proceeds to the vehicle for the area (eg, coordinate position) based on the selected pixel corresponding to the luminaire shown in the image and the first and second angles associated with the pixel position of the selected pixel. Configured to determine a position.

  The first and second angles for each pixel location in the image are determined based on a system calibration process. In some embodiments, the calibration process is accomplished by generating an image of the luminaire at a known distance and calculating an angle, such as angles α and β, for each pixel location in the received image. Once calculated, the first and second angles are assigned pixel locations in the image. The calculated angles and corresponding pixel positions are stored or made accessible to the system. In response to generating the image, the system is configured to map or otherwise associate two angles to each pixel location of the received image. Using the selected pixel and first and second angles (eg, angles α and β), the system is configured to determine the position of the vehicle relative to the area, as further described.

FIG. 16A is a schematic side view of an area showing a first angle associated with a pixel 1600 of a sensor in an embodiment of the present disclosure. The selected pixel of the received image corresponds to sensor pixel 1600. The pixel 1600 is then used to select a first angle, such as the horizontal angle α. The horizontal angle α is a known angle obtained from the calibration process described above. As shown, the pixel 1600 is located in the image plane 1602. From image plane 1602 there is a line of sight 1606 from pixel 1600 to luminaire 1100. The horizontal angle α is located between the line of sight 1606 and the center line of the sensor. A distance Z exists along the z direction of the image plane coordinate system 1604. Since the vehicle is located at a certain distance from the luminaire 1100, the distance Z is a known distance from the sensor to the luminaire 1100. The distance x0 is the ground distance along the floor of the area, for example, between the vertical projection of the luminaire 1100 to the floor of the area in the x direction of FIG. 1B and the vertical projection of the sensor centerline in the z direction. Is the distance. Using the distance Z together with the horizontal angle α for a given pixel position of the sensor corresponding to the selected pixel of the received image, the distance x0 is along the u direction with respect to the image plane 1602 using the following equation: Determined.

FIG. 16B is a schematic side view of an area showing a second angle associated with a pixel 1600 of a sensor in an embodiment of the present disclosure. It should be noted that the coordinate system 1604 has been rotated 90 degrees from the view shown in FIG. 16A. The system is configured to determine the distance y0 in a manner similar to that performed for distance x0 described above. The distance y0 is the ground distance along the floor of the area, for example, the distance between the vertical projection shifted 90 degrees as described above in the y direction of FIG. 1B. Using distance Z and a known vertical angle β for a given pixel location, distance y0 is determined as follows:

  In order to determine the orientation of the vehicle relative to the area, the system is configured to determine a plurality of distances (eg, x0 distance and y0 distance) from different luminaires within the area. These multiple distances can be combined with the position of known luminaires in the area to determine the orientation of the vehicle relative to the area. For example, x0 and y0 distances determined from a single luminaire result in at least two possible positions of the vehicle relative to the area. By determining additional x0 and y0 distances from different luminaires in the area, the system can determine the x0 and y0 distances for a predetermined number of luminaires and a determined luminaire position that indicates the vehicle orientation relative to the area. Configured to determine a unique combination of

(Further consideration)

  Many other configurations will be apparent in light of this disclosure. For example, in some embodiments of the present disclosure, the system is configured to identify multiple luminaires from a single received image. In such an embodiment, a plurality of luminaires are in the FOV of the sensor so that the received image includes a plurality of luminaires. The system is configured to determine the presence of a plurality of luminaires in the image based on pixel locations of pixels having light intensity values that are equal to or greater than a threshold, as described above. For example, the system can identify groups of pixels that have different pixel locations but have light intensity values that indicate the presence of a luminaire. In response, the system is configured to determine the identity of each luminaire in the received image using a sequential scheme. In some embodiments, the sequential scheme determines the luminaire identity based on the pixel location. For example, the system can select a group of pixels (eg, the left side) that is closest to one end of the image and first decode the VLC signal associated with those pixels. The system can continue to identify groups of pixels corresponding to the luminaire until the opposite side of the image is reached. In some embodiments, the system can select groups of pixels from top to bottom across the image. When multiple luminaires are identified in the signal image, the system is configured to determine the luminaire position for each luminaire indicated in the image, as described above. The determined position of the luminaire is used to determine the position and orientation of the vehicle relative to the area, as described above.

  In other embodiments of the present disclosure, the system further includes a backup system, such as a radio frequency (RF) system, to maintain and / or improve system performance. In some such embodiments, the RF system provides enhanced communication when the VLC signal provides limited accuracy or failure accuracy, for example, when a lighting device failure occurs. In such a case, an RF transmitter, such as an RF beacon, transmits a luminaire identifier for a given luminaire. In response, the system is configured to determine the identity of the luminaire using the luminaire position data from the RF signal and the luminaire layout information.

  In other embodiments, the system is configured to measure RF signal strength. In such an embodiment, the luminaire layout information includes a location within the area corresponding to the RF signal strength. The RF signal strength can be measured using a recorder and can be provided to the system in the form of RF signal information. RF signal information such as signal strength can be used to efficiently and accurately determine the vehicle position within the area. During operation, the vehicle measures the signal strength of the received RF signal. The vehicle then makes a request to the system to determine the vehicle position within the area (eg, (x, y) coordinate position) based on the received signal strength of the RF signal and the RF signal information for that area. Send.

  In other examples, both VLC and RF communications can be used to improve system performance. In some embodiments, for example, an RF system can be used to perform a self test to ensure the accuracy of VLC communications. In such an embodiment, the vehicle position is determined using both VLC and RF signal data. The determined vehicle positions are compared with each other to identify discrepancies in the determined vehicle positions. For example, if the determined vehicle position is within a predetermined tolerance (eg, 10 centimeters), it is not identified as a mismatch. If the vehicle position is not within a predetermined tolerance, the system is configured to further investigate the cause of the discrepancy.

  The methods and systems described herein are not limited to a particular hardware or software configuration and can find applicability in many computing or processing environments. These methods and systems may be implemented in hardware or software, or a combination of hardware and software. The method and system may be implemented in one or more computer programs, which may be understood to include one or more processor executable instructions. The computer program may be executed on one or more programmable processors, one or more storage media (including volatile and non-volatile memory and / or storage elements) readable by the processor, One or more input devices and / or one or more output devices. Thus, the processor can access one or more input devices to obtain input data and access one or more output devices to communicate output data. The input device and / or output device may include one or more of the following: RAM (Random Access Memory), RAID (Redundant Array of Independent Disks), floppy drive, CD, DVD, A magnetic disk, internal hard drive, external hard drive, memory stick, or other storage device accessible by a processor as provided herein. It should be noted that the above examples are not exhaustive and are for illustration and not limitation.

  A computer program may be implemented using one or more high-level procedural or object-oriented programming languages to communicate with a computer system. However, the program may be implemented in assembly language or machine language as required. The language can be compiled or decoded.

  As provided herein, a processor may be embedded in one or more devices that can operate independently or together in a network environment, such as a local area network (LAN). ), A wide area network (WAN), and / or an intranet and / or the Internet and / or another network. The network may be wired or wireless, or a combination thereof, and may use one or more communication protocols to facilitate communication between different processors. The processor can be configured for distributed processing, and in some embodiments, a client-server model can be utilized as needed. Thus, these methods and systems can utilize multiple processors and / or processor devices, and processor instructions may be divided into such single or multiple processors / devices.

  A device or computer system that integrates with a processor can be, for example, a personal computer, a workstation (eg, Sun, HP), a personal digital assistant (PDA), a portable device such as a mobile phone or a smartphone, a laptop , A handheld computer, or other device operable as provided herein integrated with a processor. Accordingly, the devices provided herein are not exhaustive and are provided for purposes of illustration and not limitation.

  The expressions “microprocessor” and “processor” can be understood to include one or more microprocessors that can communicate in a stand-alone and / or distributed environment. Such one or more microprocessors may be configured to communicate via wired or wireless communication with other processors, and such one or more processors may be of similar or different devices. It may be configured to operate on one or more processor control devices. Thus, the use of the term “microprocessor” or “processor” can be understood to include central processing units, arithmetic logic units, application specific integrated circuits (ICs) and / or task engines, These examples are illustrative and not limiting.

  Further, the term memory may include one or more processor-readable and accessible memory elements and / or components, unless specified otherwise, that are internal to the device controlled by the processor. May be external to the processor control device and / or accessed via a wired or wireless network using various communication protocols. Also, unless otherwise noted, it may be configured to include a combination of external and internal memory devices, and such memory may be continuous and / or partitioned based on the application. Thus, a database notation can be understood to include one or more memory collections, such a notation being a commercially available database product (eg, SQL, Informix, Oracle) or private And a structure for assembling memory, such as links, matrices, graphs, and trees. Note that these structures are illustrative and not limiting.

  Reference to a network can include one or more intranets and / or the Internet unless otherwise specified. Reference to microprocessor instructions or microprocessor-executable instructions may be understood to include programmable hardware according to the above.

  Unless otherwise noted, use of the term “substantially” includes precise relationships, conditions, arrangements, orientations, and / or other features, and deviations thereof, as will be appreciated by those skilled in the art. Can be interpreted. Deviations are such that they do not significantly affect the disclosed methods and systems.

  Throughout this disclosure, the use of the articles “a” (one) and / or “an” (one) and / or “the” (this) to modify nouns is understood to be used for convenience. And unless otherwise specified, is understood to include one or more of the modified nouns. The terms “comprising”, “comprising” and “having” are inclusive and mean that there may be additional elements other than the listed elements.

  Elements, components, modules, and / or parts thereof that are described throughout the drawings and / or otherwise depicted, communicated with, associated with, and / or based on, Unless otherwise specified, it is understood to communicate, associate, or be based on direct and / or indirect methods.

  Although the above methods and systems have been described in connection with specific embodiments, they are not limited thereto. Many modifications and variations are apparent in light of the above teaching. Those skilled in the art will be able to make many additional changes in the details, materials, and arrangement of parts described and illustrated herein.

Claims (24)

A method for determining the position of a vehicle in an area,
Receiving an image of an asymmetric reference pattern displayed by a luminaire in the area;
Determining a coordinate position of the luminaire based on the received image of the asymmetric reference pattern displayed by the luminaire;
Determining an orientation of the vehicle relative to the area based on an orientation of the asymmetric reference pattern in the received image;
Determining the position of the vehicle relative to the area based at least in part on the determined coordinate position of the luminaire.   The method of claim 1, wherein determining the position of the vehicle relative to the area is based at least in part on the position of the vehicle relative to the luminaire.   The method of claim 1, wherein the determination of the position of the vehicle within the area is based on a single received image of the asymmetric reference pattern displayed by the luminaire.   The method of claim 1, wherein determining the orientation of the vehicle relative to the area comprises associating asymmetry of the asymmetric reference pattern with a direction relative to the area.   The method of claim 1, wherein the determination of the coordinate position of the luminaire within the area is based on a luminaire identifier obtained from a received image of the asymmetric reference pattern.   The method of claim 1, wherein determining the position of the vehicle relative to the luminaire includes converting the determined coordinate position of the luminaire from a three-dimensional coordinate position to a two-dimensional position.   The position of the vehicle with respect to the lighting fixture is projected from the three-dimensional coordinate position of the lighting fixture on a sensor image plane along a projection line from the three-dimensional coordinate position of the lighting fixture to the sensor. The method according to claim 6, wherein the three-dimensional coordinate position is converted into the two-dimensional position. A system for determining the position of a vehicle in an area,
A luminaire comprising a plurality of light sources configured to display an asymmetric reference pattern, wherein the asymmetric reference pattern indicates an orientation of the luminaire with respect to the area;
A sensor disposed on the vehicle configured to receive an image of the asymmetric reference pattern;
A processor for determining the in-area position of the luminaire based on the received image of the asymmetric reference pattern;
Determining the orientation of the vehicle relative to the area based on the received image of the asymmetric reference pattern;
A system comprising: a processor configured to determine a position of the vehicle within the area based at least in part on the determined position of the luminaire and the orientation of the vehicle relative to the determined area.   The system of claim 8, wherein the position of the vehicle within the area is based at least in part on a vehicle position relative to the luminaire.   The system of claim 8, wherein the vehicle is an autonomous vehicle configured to navigate the area using an image of the asymmetric reference pattern displayed by the luminaire.   The asymmetric reference pattern is associated with a luminaire identifier, and the processor decodes the pattern based on a light intensity value of one or more pixels of the received image to determine the luminaire identifier. 9. The system of claim 8, wherein the system is capable of.   The system of claim 8, wherein the processor is further configured to associate an asymmetry of the asymmetric reference pattern with a direction relative to the area.   The said luminaire includes a combination of an infrared light source and a visible light source, the asymmetric reference pattern is displayed using the infrared light source, and the area is illuminated using the visible light source. system.   The system of claim 8, further comprising a computing system that communicates with at least one of a plurality of lighting fixtures and the vehicle via a network.   The system of claim 8, wherein the processor determines a position of the vehicle within the area based on a single image of the asymmetric reference pattern. A method for determining the position of a vehicle in an area,
Receiving a first image of a first luminaire in a first position within the area, the first image including a first visible light communication signal from the first luminaire;
Receiving a second image of a second luminaire at a second position different from the first position in the area, wherein the second image includes a second visible light communication signal from the second luminaire;
Determining the first position of the first lighting device in the area based on the first visible light communication signal displayed in the first image;
Determining the second position of the second lighting fixture in the area based on the second visible light communication signal displayed in the second image;
Determining the position of the vehicle relative to the area based on the determined first and second positions and at least one selected pixel of the first and second images.   The selected pixel of at least one of the first and second images is a pixel located at a central pixel position of at least one of the first and second luminaires displayed in the first and second images. The method of claim 16, wherein the method is determined based on: Determining the position of the vehicle relative to the area further comprises:
Associating a first angle and a second angle with at least one selected pixel of the first and second images corresponding respectively to at least one of the first and second luminaires;
Determining a first distance in a first direction from the vehicle to the lighting fixture based on the first angle;
Determining a second distance in a second direction from the vehicle to the luminaire based on the second angle;
The position of the vehicle with respect to the lighting fixture may be determined based on at least one position of the determined first and second lighting fixtures, the first distance, and the second distance. The method described. Determining the first position of the first luminaire within the area further comprises:
Determining a portion of the first image that includes the first lighting fixture;
Analyzing the portion of the first image that includes the first luminaire to identify a visible light communication signal for the first luminaire, the visible light communication signal being encoded by a luminaire identifier; When,
The method of claim 16, comprising determining a position of the first luminaire based on the luminaire identifier.   The portion of the first image is based on comparing a light intensity value of an individual pixel of the first image with a threshold value that distinguishes pixels associated with a background object and pixels associated with one or more luminaires. 20. The method of claim 19, wherein the method is determined. Determining the position of the luminaire using the luminaire identifier;
The lighting fixture layout information in the area is received, and the coordinate position of the lighting fixture in the area is determined by comparing the lighting fixture identifier and the lighting fixture layout information to identify the coordinate position of the lighting fixture. 20. The method of claim 19, comprising:   The step of determining the position of the vehicle relative to the area includes determining an orientation of the vehicle relative to the area based on a first position of the first lighting fixture and a second position of the second lighting fixture. 16. The method according to 16.   The method of claim 16, wherein determining the position of the vehicle relative to the area is based on a known distance between at least one of the first and second luminaires and a sensor disposed on the vehicle. A method for determining the position of a vehicle in an area,
Receiving an image of the area, the image including a first luminaire displaying a first visible light communication (VLC) signal and a second luminaire displaying a second VLC signal;
Determining a first pixel group of the image corresponding to the first lighting fixture;
Determining a second pixel group of the image corresponding to the second lighting fixture;
Determining a first position of the first luminaire in the area based on the first VLC signal corresponding to the first pixel group of the image;
Determining a second position of the second luminaire in the area based on the second VLC signal corresponding to the second group of pixels of the image;
Determining an orientation of the vehicle relative to the area based on the determined first and second positions;
Determining a position of the vehicle relative to the area based on at least one of the determined first and second positions and a pixel selected from one of the first and second pixel groups of the image; A method comprising the steps of:

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